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A Beckers

Publications and source records attributed to A Beckers.

At least 55 records · Page 3Linked to original sources
PubMed1999

[An immunologic etiology for hyperprolactinemia: macroprolactinemia].

Besides classical etiologies of hyperprolactinaemia (pregnancy, pharmacological treatments, pituitary or hypothalamic perturbations), another less known cause may explain a spectacular idiopathic elevation of plasma concentrations of prolactin hormone. Macroprolactinaemia is characterized by the presence of a circulating high molecular weight complex of prolactin with an immunoglobulin G. In this article, we report the cases of 3 female patients for whom size exclusion chromatography technique permitted to give a precise biological diagnosis and to avoid heavy, expensive, time consuming and unnecessary clinical investigations or therapeutic actions. Patients with macroprolactinaemia do not exhibit clinical features of classical hyperprolactinaemia, notably as regard to menstrual and fertility disturbances.

Adult↗
PubMed1998

Mechanical strain at the pisotriquetral joint.

Pain and tenderness on the palmar and ulnar aspects of the wrist in the area of the pisiform bone is fairly common. Chronic pain in the pisiform area may be due to tendinitis of the insertion of the flexor carpi ulnaris, bony fractures or osteoarthrosis of pisotriquetral joint which is the second most common degenerative arthritis in wrist after the scaphotrapezial osteoarthrosis (Fischer, 1988, Radiologe 28:338-344). Subperiostal excision of pisiform bone is customarily performed after unsuccessful initial non-operative treatment (Carroll and Coyle, 1985, J. Hand Surg. 10:703-707; Johnston and Tonkin, 1986, Clin. Orthop. 210:137-142; Nüesch et al., 1993, Handchir. Mikrochir. Plast. Chir. 25:42-45). Although the postoperative results seem to be rather good, possible malfunction based on excision has not been considered previously by investigators. The aim of this study was to improve our understanding of the role of the pisiform and the pisotriquetral joint in the transfer of forces within the carpus. In a first part we examined 112 pisotriquetral joints by qualitative, quantitative and densitometrical analysis of joint surfaces. Secondly, mechanical tests were performed to investigate the distribution of forces within pisiform and the pisotriquetral joint. The results demonstrate that the pisiform mechanically contributes to the stability of the ulnar column of the wrist. The pisiform, and its unique anatomical holding mechanism, discharges two main functions. It holds the triquetrum in a correct position and prevents its subluxation even in extreme extension. Furthermore, it acts as a fulcrum (hypomochlion) while transducing powerful forearm forces to the hand. The excision of pisiform should be reconsidered.

Aged↗
PubMed1998

Comparative densitometric study of iliac crest and scapula bone in relation to osseous integrated dental implants in microvascular mandibular reconstruction.

The study was designed to compare dimension and density of four frequently used bone donor regions (the iliac crest, the lateral border of the scapula, the radius and the fibula) with regard to placement of endosseous dental implants in microvascular mandibular reconstruction. The first part of the study reports on the results of bone dimension and density findings for iliac crest and scapula bone. Nearly all of the iliac crests had adequate dimensions for the positioning of four 10 mm implants. In 63% of the scapulae, it was possible to place four 10 mm implants. In the case of the scapula, half of the female subjects lacked enough available bone for the insertion of four 10 mm implants because of their inadequate width. Bone density and cortical thickness was found to be similar in the iliac crest and scapula. Age and side do not have an important influence on cortical bone dimensions and density. In contrast to the iliac crest, the lateral margin of the scapula astonishingly showed increasing values for bone density and increasing thickness of the cortex. Analogical advanced biological age works in conformity with the scapula flap. The results could, together with other clinical criteria, contribute to the choice of the best individual alternative in mandibular reconstruction.

Adult↗
PubMed1998

Cabergoline in the treatment of acromegaly: a study in 64 patients.

Cabergoline is a new, long acting, dopamine agonist that is more effective and better tolerated than bromocriptine in patients with hyperprolactinemia. Because dopamine agonists still have a place in the medical management of acromegaly, cabergoline might be a useful treatment. We, therefore, evaluated the effect of long term administration of cabergoline in a large group of unselected acromegalic patients. Sixty-four patients were included in a multicenter, prospective, open labeled study. A subgroup of 16 patients had GH-/PRL-cosecreting pituitary adenomas. Cabergoline was started at a dose of 1.0 mg/week and was gradually increased until normalization of plasma insulin-like growth factor I (IGF-I) levels, occurrence of unacceptable side-effects, or a maximal weekly dose of 3.5 mg (7.0 mg in 1 case) was reached. Treatment with cabergoline suppressed plasma IGF-I below 300 micrograms/L in 39% of cases and between 300-450 micrograms/L in another 28%. With pretreatment plasma IGF-I concentrations less than 750 micrograms/L, a suppression of IGF-I below 300 micrograms/L was obtained in 53% of cases, and a suppression between 300-450 micrograms/L was obtained in another 32%. By contrast, with pretreatment plasma IGF-I concentrations above 750 micrograms/L, only 17% of cases showed a suppression of IGF-I below 300 micrograms/L, and there was IGF-I suppression between 300-450 micrograms/L in another 21%. In GH-/PRL-cosecreting adenomas, 50% of cases suppressed plasma IGF-I levels below 300 micrograms/L, and another 31% did so between 300-450 micrograms/L, in contrast to only 35% and 27%, respectively in GH-secreting adenomas. Similar results were obtained concerning the secretion of GH. Tumor shrinkage was demonstrated in 13 of 21 patients, with a mass reduction by more than half in 5 GH-/PRL-cosecreting adenomas. Except for slight gastrointestinal discomfort and orthostatic hypotension in a few patients at the beginning of therapy, cabergoline treatment was well tolerated. Only 2 patients stopped medication because of nausea. The weekly dose of cabergoline ranged between 1.0-1.75 mg. A further increase in the dose was only effective in 1 GH-/PRL-cosecreting adenoma. The results of this study suggest that cabergoline is an effective, well tolerated therapy that should be considered in the management of acromegaly, especially if the pituitary adenoma cosecretes GH and PRL or if pretreatment plasma IGF-I levels are below 750 micrograms/L.

Acromegaly↗
PubMed1998

Mutation analysis of the MEN1 gene in multiple endocrine neoplasia type 1, familial acromegaly and familial isolated hyperparathyroidism.

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant disease characterized by neoplasia of the parathyroid glands, the endocrine pancreas, and the anterior pituitary gland. In addition, families with isolated endocrine neoplasia, notably familial isolated hyperparathyroidism (FIHP) and familial acromegaly, have also been reported. However, whether these families constitute MEN 1 variants or separate entities remains speculative as the genetic bases for these diseases are unclear. The gene for MEN 1 has recently been cloned and characterized. Using single strand conformation analysis (SSCA) and sequencing, we performed mutation analysis in: a) a total of 55 MEN 1 families from 7 countries, b) 13 isolated MEN 1 cases without family history of the disease, c) 8 acromegaly families, and d) 4 FIHP families. Mutations were identified in 27 MEN 1 families and 9 isolated cases. The 22 different mutations spread across most of the 9 translated exons and included frameshift (11), nonsense (6), splice (2), missense mutations (2), and in-frame deletions (1). Among the 19 Finnish MEN 1 probands, a 1466del12 mutation was identified in 6 families with identical 11q13 haplotypes and in 2 isolated cases indicating a common founder. One frameshift mutation caused by 359del4 (GTCT) was found in 1 isolated case and 4 kindreds of different origin and haplotypes; this mutation therefore represents a common "warm" spot in the MEN1 gene. By analyzing the DNA of the parents of an isolated case one mutation was confirmed to be de novo. No mutation was found in any of the acromegaly and small FIHP families, suggesting that genetic defects other than the MEN1 gene might be involved and that additional such families need to be analyzed.

Acromegaly↗
PubMed1998

The burden of illness of hypopituitary adults with growth hormone deficiency.

OBJECTIVE: The negative metabolic and psychosocial consequences of growth hormone deficiency (GHD) in adults are now well established. In the present study, an attempt was made to quantify the burden of illness, in terms of lost productivity and increased medical consumption, associated with hypopituitarism and untreated GHD. DESIGN AND SETTING: The study population consisted of 129 Belgian adults with untreated GHD associated with hypopituitarism after pituitary surgery. The Short-Form 36 Health Survey (SF-36) was used to assess health status, and the Health and Labour Questionnaire was used to measure production losses and labour performance. Data on medical consumption were also collected. MAIN OUTCOME MEASURES AND RESULTS: Hypopituitary patients reported a lower health status than that of the general population in all but two dimensions of the SF-36 (pain and physical functioning). Nearly 11% of the patients reported being incapacitated for paid employment due to health problems, compared with 4.8% of the general Belgian population. Patients in paid employment reported a mean of 19.8 days of sickness leave per year, which is twice that in the general population. The annual number of visits to general practitioners and specialists was also higher in the patients (9.6 and 6.5 visits, respectively, for the patients compared with corresponding figures of 2.1 and 1.5 for the general Belgian population). The average annual number of days spent in hospital was 3.5 for the patients compared with 2.3 in the general population. The annual healthcare costs and costs due to production losses calculated for hypopituitary patients who had received pituitary surgery amounted to 135,024 Belgian francs (BeF) or $US4340 (1995 values). This compares with the mean annual cost per person for the Belgian population as a whole of BeF68,569 or $US2204. CONCLUSIONS: Hypopituitary patients with untreated GHD therefore have a higher cost to society in terms of lost production and medical consumption than the average Belgian population.

Adult↗
PubMed1998

[Clinical case of the month. A male with 46,XX karyotype].

The XX males represent a rare expression of the Klinefelter syndrome associated with hypergonadotropic hypogonadism. Generally the patients are of small stature with normal secondary sexual male features but with small testes and constant sterility. The plasma concentrations of FSH and LH are very high in accordance with the decrease of the testicular function. From the genetic point of view, the XX males may be divided in 3 groups: 1) in 80% of cases, the XX males bear the SRY gene and exhibit a XY translation during the paternal meiosis with the presence of the SRY gene on one of the X chromosomes as a marker of the male differentiation; 2) in 10% of cases, the males are (SRY-)XX; the abnormal development is then due to other genes than the TDF, which, when mutated, can induce sexual male differentiation. The remaining 10% of cases are due to chromosomal mosaïcism with more XX than XY.

Adult↗
PubMed1998

[Genetic aspects of the 46, XX male].

The XX males represent a proportion of 1/25 of all patients suffering of the Klinefelter syndrome. From a clinical and endocrinological point of view, they exhibit a hypogonadotropic hypogonadism. Isolated cases are rare and familial forms are exceptional. The XX males may be divided in 3 subgroups: 46, XX males with the SRY gene; 46, XX males without the SRY gene and XX/XY mosaics.

Crossing Over, Genetic↗
PubMed1998

[How I study thyroid pathology using ultrasonography-guided needle biopsy].

From a retrospective study of 259 files, the authors stress the value of US-guided thyroid cytoponction and its essential role in case of thyroid cancer suspicion. This very specific and inexpensive method fits perfectly into the other exploration techniques. It is the deciding factor in the thyroid nodule differential diagnostic and therapeutic planning.

Adenocarcinoma, Follicular↗
PubMed1997

125I-Tyr0-hCRH labelling characteristics of corticotropin-releasing hormone receptors: differences between normal and adenomatous corticotrophs.

The presence of corticotropin-releasing hormone (CRH) receptors has been previously demonstrated in corticotrophs from normal pituitaries using a method combining immunocytochemistry and liquid emulsion autoradiography. The aim of this study was to compare the characteristics of the 125I-Tyr0-hCRH binding in corticotrophs from normal pituitaries (three obtained at autopsy and one obtained at surgery) with corticotrophs from pituitary adenomas (six corticotroph adenomas responsible for Cushing's disease and two silent corticotroph adenomas secreting a biologically inactive ACTH molecule). In normal corticotrophs, the larger part of the 125I-Tyr0-hCRH binding was localised in patchy conglomerates at the centre of the cell and, to a much lesser degree, in a diffuse pattern at the cell periphery. In adenomatous corticotrophs, CRH receptor expression is disturbed both quantitatively and qualitatively. Except for a minority of cells in one adenoma, all adenomatous corticotrophs showed only peripherally bound 125I-Tyr0-hCRH and no centrally localised binding. Furthermore, adenomatous corticotrophs revealed a statistically significant lower signal intensity when compared to normal corticotrophs and a strongly negative correlation was found between the labelling area in adenomatous corticotrophs and both the basal and CRH-stimulated plasma ACTH levels. These findings suggest defective processing of CRH receptors and could be relevant to the sustained ACTH secretion by adenomatous corticotrophs in Cushing's disease and, more generally, provide an explanation to its pathology. The silent corticotrophs secreting a biologically inactive ACTH molecule were characterised by a very faint signal intensity, although present on almost every cell.

Adenoma↗
PubMed1997

Two years of replacement therapy in adults with growth hormone deficiency.

OBJECTIVES: Although several studies have shown beneficial short-term effects of recombinant human growth hormone (rhGH) therapy in adult GH deficient (GHD) patients, few data are available on large groups of patients treated for more than one year. In addition, the optimal dose of rhGH for each patient and the baseline parameters that predict which patients will benefit most from therapy or will have adverse events are not entirely elucidated. DESIGN: 148 adult GHD patients were enrolled in a multicentre 2-year rhGH replacement study which was placebo controlled for the first six months. rhGH (Genotropin/Genotonorm Pharmacia & Upjohn) was given in a dose of 0.25 IU/kg/week sc (1.5 IU/m2/day). MEASUREMENTS: Every 3-6 months body composition was measured using body impedance analysis and general well being was assessed using the Nottingham Health Profile (NHP) and social self-reporting questionnaire. At the same time patients had a full clinical examination and blood was sampled for glucose, HbA1c, IGF-1, creatinine, full blood count, thyroid hormones and liver function tests. RESULTS: With rhGH therapy IGF-1 levels increased from -2.00 +/- 2.60 SDS to 1.47 +/- 2.6 SDS after six months (P < 0.001), continued to rise despite no change in dose to 1.84 +/- 2.8 SDS after one year and remained constant thereafter (1.98 +/- 2.4 after 2 years). 56% of patients ultimately attained supranormal IGF-1 levels (+2 SD), 22% had levels below the mean, of which 9% were below -2 SD. Within 3 months lean body mass (LBM) increased by +5.09% (P < 0.001), total body water (TBW) by +5.40% (P < 0.001), while body fat (BF) dropped by -10.89% (P < 0.001) and waist circumference by -1.42% (P < 0.004). These effects were maintained during the first year of therapy, but the effect was attenuated after 24 months: LBM, +3.91% (P < 0.001); TBW, +3.28%, P < 0.001, BF, -6.42% (P < 0.001) and waist -2.22% (P < 0.009). Individual differences in response were large and could not be predicted by any of the baseline parameters, except for a better response in males. Treatment resulted in a large and progressive improvement on the NHP scale, especially energy, emotions and sleep, but a similar change was also found in patients during placebo treatment. With rhGH the number of full days of sick leave/6 months decreased from 12.17 +/- 3.90 days (SEM) to 7.15 +/- 3.50 days after six months (P = 0.009), 2.93 +/- 1.55 days after 12 months (P = 0.01), 0.39 +/- 0.17 days after 18 months (P < 0.001) and 3.3 +/- 2.51 days after 24 months (P = 0.026). Similarly, the hospitalization rate went down from 14.9 to 7% after 6 months and remained at this level thereafter (P = 0.12). About one third of patients on rhGH experienced fluid-related adverse events, most often within the first 3 months. They usually disappeared spontaneously or responded well to dose reduction. Cumulative dropout rates were 29% after 1 year and 38% after two years. Two thirds of these patients stopped treatment because of insufficient subjective improvement. Neither drop-outs nor fluid retention could not be predicted by any of the baseline parameters. CONCLUSIONS: We confirmed in a large group of patients the beneficial effects of rhGH therapy on body composition, metabolic parameters and general well-being and found a consistent drop in number of sick days and hospitalization rate. These effects were maintained during two years of therapy, except for an attenuation in body composition changes after 24 months. The high incidence of fluid-related adverse events suggests that it may be better to start with lower doses of rhGH and to increase the dose more slowly over a number of weeks. The finding of suboptimal high or low IGF-1 levels in many patients reinforces guidelines not to give rhGH in a weight-dependent dose but to titrate it individually for each patient.

Adult↗
PubMed1997

Expression of somatostatin receptor SST4 in human placenta and absence of octreotide effect on human placental growth hormone concentration during pregnancy.

In pregnancy, the human placenta GH acts as a growth-promoting hormone and appears to be the main stimulator of insulin-like growth factor I (IGF-I) secretion. In a woman with a TSH-secreting macroadenoma, successful treatment with the somatostatin analog octreotide was conducted during the first month and the second half of pregnancy without side-effects on placental and fetal development. As observed in normal pregnancy, both serum placental GH and IGF-I levels increased throughout pregnancy and dropped sharply after delivery. In placental membranes from both treated and healthy untreated patients, we demonstrated the presence of high affinity binding sites for somatostatin-14 (Kd, 4.6 and 5.3 nmol/L; binding capacity, 1.53 and 1.35 pmol/mg protein, respectively). These receptors displayed low affinity for octreotide (IC50, 1.2-2 mumol/L), suggesting the presence of SST1 and/or SST4 receptors. We found that messenger ribonucleic acids of these two subtypes were expressed in both human placental tissue and purified human cytotrophoblast cells. Finally, the SST1-selective analog, des-AA1,2,5[D-Trp8,IAmp9]S-14 had low affinity for placental somatostatin receptors. These results argue in favor of the presence of the SST4 subtype in human placenta. At the doses administered, octreotide did not bind to placental somatostatin receptors. Our results may explain the absence of changes in both human placental GH and IGF-I concentrations that we observed during octreotide treatment.

Adenoma↗
PubMed1997

[Intra-sellar non-adenomatous expansive process].

More than thirty types of tumors in the sellar region can mimic pituitary adenoma on, magnetic resonance imaging. When they exist, clinical manifestations are not necessarily highly contributive to diagnosis. Headache, visual impairment, signs of antepituitary insufficiency or possible dysmenorrhea with galactorrhea attributed to hyperprolactinemia due to compression of the dopaminergic axis are not specific and may be misleading. Clinical signs of diabetes insipidis and polyphagia are however suggestive of non-pituitary tumors. Consequently, high-resolution imaging (MRI) and sometimes particular diagnostic circumstances (post partum for hypophysitis for example, or breast cancer for metastasis) orient the diagnosis. More rarely tumor enlargement, for example in certain germ cell tumors, provides a clue.

Adolescent↗
PubMed1997

Mesenteric venous thrombosis. Diagnostic and therapeutic approach.

Mesenteric venous thrombosis is an infrequent but distinct form of intestinal ischaemia. We report a case of acute mesenteric venous thrombosis diagnosed by computed tomography. Laparoscopy permitted to establish the extent of the ischaemia. Initially, high doses streptokinase were administered for 6 hours, followed by heparinotherapy for 10 hours, with the aim to reduce the length of bowel to be resected. One day later, intestinal resection was carried out, followed by postoperative anticoagulation.

Adult↗
PubMed1996

Presurgical Octreotide: treatment in acromegaly.

One hundred seventy-two acromegalics who were operated on using the trans-sphenoidal approach underwent long-term follow-up evaluation. Sixty-four received 100 micrograms octreotide subcutaneously three times daily: for 3 to 6 weeks before surgery in 14 patients (group 1); and for 3 to 9 months in 41 and for 13 to 39 months in nine (n = 50, group 2). In 18 group 2 patients, the dose was increased stepwise to 500 micrograms three times daily because of incomplete suppression of growth hormone (GH)/insulin-like growth factor-1 (IGF-1). Tumor shrinkage was seen in 60% within 3 weeks, being nearly maximal by 3 to 4 months. More group 2 patients had greater than 25% tumor shrinkage (14 of 48 v 1 of 14 in group 1). Clinical response was excellent or good in 89%. Decrease in soft-tissue swelling and weight loss, and improved vitality, performance, carbohydrate metabolism, and cardiovascular function, facilitated anesthetic and surgical management; tumor removal was easy in virtually all cases. In all 64 patients, GH levels decreased by > or = 50%, and to < 2 micrograms/L in three of 14 patients initially and 25 of 50 patients after more prolonged treatment. IGF-1 levels decreased to normal in seven of 14 group 1 and 31 of 50 group 2 patients. Light and electron microscopy showed that adenomatous tissue exposed to octreotide had lysosomal accumulation, amyloid deposition, mild to moderate perivascular fibrosis, and moderate size reduction in both cytoplasmic and nuclear areas, with virtually no cellular complications. Remission with enclosed adenomas was greater (p < .05) than for the 108 patients not treated with octreotide; there was no difference for invasive adenomas. Octreotide use for 3 to 4 months before surgery can be recommended.

Acromegaly↗
PubMed1995

The effect of naloxone and metoclopramide on the secretion of luteinizing hormone in a hyperprolactinemic hypogonadotropic postmenopausal woman.

OBJECTIVE: To determine the role of opioidergic and dopaminergic activity in the suppression of GnRH0LH in a hyperprolactinemic state. DESIGN: Case report. SETTING: University hospital. PATIENT: A 68-year-old woman with a macroprolactinoma. INTERVENTIONS: Serial 10-hour IV infusions of naloxone and metoclopramide. MAIN OUTCOME MEASURE: Serum LH concentration. RESULTS: Naloxone induced a small but significant rise of serum LH levels, which displayed a pulsatile pattern. By contrast, metoclopramide elicited no significant response in LH secretion. CONCLUSION: Opioidergic but not dopaminergic neurotransmission plays a direct role in the suppression of LH secondary to hyperprolactinemia.

Aged↗