Search PubMed⌕ Search

Biomedical subjects

E Lajeunie

Publications and source records attributed to E Lajeunie.

At least 37 records · Page 2Linked to original sources

Jackson-Weiss syndrome: identification of two novel FGFR2 missense mutations shared with Crouzon and Pfeiffer craniosynostotic disorders.

Jackson-Weiss syndrome is a rare skeletal disorder characterized by craniosynostosis associated with foot malformations. This condition is inherited as an autosomal dominant trait with complete penetrance and wide phenotypic heterogeneity. Mutations in the fibroblast growth factor receptor 2 (FGFR2) gene have been recently identified as causes of this syndrome and of at least four other craniosynostotic disorders, namely the Apert, Beare-Stevenson cutis gyrata, Crouzon and Pfeiffer syndromes. We report two novel FGFR2 missense mutations associated with phenotypes consistent with Jackson-Weiss syndrome. Both nucleotide changes predict a serine for cysteine-342 substitution in the second half of the third immunoglobulin-like domain. The replacement of Cys342 with arginine has previously been reported in one of the three Jackson-Weiss cases investigated. Interestingly, both Cys342Ser and Cys342Arg substitutions have been found to be associated with the Crouzon and Pfeiffer phenotypes; a phenotypic heterogeneity, Crouzon vs Jackson-Weiss clinical features, has been also observed for Gln289Pro and Ala344Gly amino-acid changes. This finding indicates the genetic homogeneity of the "heterogeneous" Jackson-Weiss phenotype and a common molecular basis for these apparently "clinically distinct" craniosynostotic disorders.

Acrocephalosyndactylia↗

[Anesthesia and intensive care of craniostenosis and craniofacial dysmorphism in children].

Craniosynostosis occurs in one out of 2,000 births. It results in primary skull deformations requiring surgical repair, in infants with a body weight of less than 10 kg. Pure craniosynostosis is the most frequent situation, where the risk for cerebral compression during brain development is the lowest. Therefore the aim of surgical correction in this case is mainly cosmetic. Conversely, in syndromic craniosynostosis, associated malformations are more common and cerebral, visual and respiratory consequences of complex facio-craniosynostosis are usually severe. Current surgical techniques consist of a total skull vault reconstruction which carry a high risk of sudden and major blood losses. Intraoperatively, whatever the type of craniosynostosis, mean blood losses corresponding to 90% of estimated red cell mass have to be anticipated. These blood losses vary according to the type of skull deformation and the type of surgery. Accurate evaluation is usually difficult and must be based more on calculation of red cell mass variations than on simple monitoring of surgical drainage. Invasive haemodynamic monitoring is always required. To reduce the amount of homologous blood transfusion, peroperative haemodilution seems to be the most suitable technique, due to unresolved technical difficulties in autotransfusion practice in infants. Severe facial deformities are associated with chronic hypoxaemia and cerebral compression representing major risk for these children in poor condition undergoing such major surgical procedures. With experienced teams, this high-risk surgery carries a low peroperative mortality (less than 1%) and morbidity rate. The latter includes essentially transient peroperative hypotension. The excellent final cosmetic and functional results justify the practice of this surgery in children with a bodyweight of less than 10 kg.

Anesthesia, General↗

[Oxycephaly, a severe craniosynostosis. Apropos of a series of 129 cases].

AIMS: The authors analyse a series of patients with oxycephaly in order to detail the definition of this craniosynostosis and its functional prognosis. PATIENTS AND METHODS: The medical records of 129 oxycephalic patients were reviewed. Skull X-rays, ophthalmologic examination, mental level assessment, intracranial pressure monitoring and CT scan were analysed. The more recent patients were also analysed by MRI. Operated on or not, the patients were followed-up, particularly as far as the mental evolution is concerned. Mean follow-up was 3 years 7 months. RESULTS: One third of the patients came from North Africa, where oxycephaly seems predominant. Mean age at diagnosis was 6 years. Past history of rickets was found in 15% of the patients. On X-rays, the vast majority of the patients presented with multisutural synostosis involving both coronal and sagittal sutures, and diffuse digital prints. At the first mental assessment, one third of the patients had an IQ below 80. Papilledema was found in 17%. The monitoring of intracranial pressure showed an increased pressure in almost two thirds of the patients. Sixty-four percent of the patients with increased intracranial pressure had a normal fundoscopy. Out of 16 patients explored by MRI, 12 had a Chiari I malformation. Postoperatively, all papilledemas disappeared, and the intracranial pressure returned to normal in all cases with preoperative increased intracranial pressure. The mental level seemed to stabilize, the mean postoperative IQ being strongly correlated with the preoperative level. In non-operated patients, the mental level worsened significantly. CONCLUSIONS: Oxycephaly is a late-appearing craniosynostosis, with a high risk of ophthalmologic and mental complications. Based on the present series, the operation seemed effective in preventing these complications.

Adolescent↗

Mutations of the TWIST gene in the Saethre-Chotzen syndrome.

Saethre-Chotzen syndrome (acrocephalo-syndactyly type III, ACS III) is an autosomal dominant craniosynostosis with brachydactyly, soft tissue syndactyly and facial dysmorphism including ptosis, facial asymmetry and prominent ear crura. ACS III has been mapped to chromosome 7p21-22. Of interest, TWIST, the human counterpart of the murine Twist gene, has been localized on chromosome 7p21 as well. The Twist gene product is a transcription factor containing a basic helix-loop-helix (b-HLH) domain, required in head mesenchyme for cranial neural tube morphogenesis in mice. The co-localisation of ACS III and TWIST prompted us to screen ACS III patients for TWIST gene mutations especially as mice heterozygous for Twist null mutations displayed skull defects and duplication of hind leg digits. Here, we report 21-bp insertions and nonsense mutations of the TWIST gene (S127X, E130X) in seven ACS III probands and describe impairment of head mesenchyme induction by TWIST as a novel pathophysiological mechanism in human craniosynostoses.

Acrocephalosyndactylia↗

[Genetics of craniofacial malformations].

The most frequent craniofaciosynostoses, Crouzon, Apert and Pfeiffer syndromes, are due to mutations of genes coding for FGF growth factor receptors (FGFR). The Twist gene has been recently implicated in Saethre-Chotzen syndrome. The current confusion concerning phenotypegenotype correlation is starting to be clarified by the increasing number of cases in which the mutations have been identified and the clinical classification will need to be revised in the light of the results of molecular genetics.

Craniofacial Abnormalities↗

[Mental prognosis of trigonocephaly and therapeutic implications].

The authors assessed the long-term mental prognosis of trigonocephaly, in a series of 76 operated cases. Mental prognosis factors were studied, showing that early cranial release and reconstruction were effective. Final assessment of mental development was performed on children of school age, and was based on the development of behavioral disturbances, learning disability, school difficulties, and intellectual efficiency. Children were graded into 3 groups: no abnormality, mild abnormalities with normal socialization, major abnormalities; 31.6% presented disorders. Preoperative C-T scans assessed the severity of the cranial deformity and identified associated intracranial abnormalities, such as agenesis of the corpus callosum, dilatation of the subdural spaces, or hydrocephalus. Associated extracranial malformations, and associated family cases were also noted. Finally, the quality of the family context was studied. Several correlations were identified; mental development was correlated with the severity of frontal stenosis, the age at surgery and the associated extracranial malformations. Family environment also had a major influence. Intracranial abnormalities were not correlated with mental development.

Child, Preschool↗

[Antley-Bixler syndrome. Description of two new cases and review of the literature. Prognostic and therapeutic aspects].

Antley-Bixler syndrome was first described in 1975, and to date, 20 cases have been reported. In addition to brachycephaly, the syndrome is associated with midface hypoplasia often with choanal stenosis or atresia, bilateral radiohumeral synostosis, multiple joint contractures, femoral bowing and long bone fractures, "pear-shaped nose", dysplasic ears, and occasionally urogenital or cardiac defects. Survival is closely linked to upper airway obstruction, which also affects (with craniosynostosis) mental prognosis. Association and severity of malformations are variable, and while numerous children have died early from respiratory distress, one third of them are alive, and have had quite satisfactory development. With early and effective prevention of respiratory complications, and early treatment of craniosynostosis, overall prognosis can be favorable. The mode of inheritance is probably autosomal recessive and midtrimester prenatal diagnosis is feasible; genetic counseling depends on accurate prognostic and therapeutic data. We describe 2 further cases. The first a 4 years old male, with unilateral coronal synostosis and radiohumeral synostosis predominating on the same side. The second an 18 months old female, with brachycephaly and an imperforate anus.

Abnormalities, Multiple↗

Genetic study of scaphocephaly.

From a series of 1,408 patients with craniosynostosis hospitalized between 1976 and 1994, 561 probands with non-syndromal isolated sagittal synostosis were analyzed. The prevalence of sagittal synostosis was estimated in the order of 1 in 5,000 children. Family information was obtained from 373 probands distributed among 366 families. The male:female ratio was 3.5:1. There was no maternal or paternal age effect. In 22 of the 366 pedigrees, a high degree of familial aggregation was observed, giving a 6% figure of familial cases. Segregation analysis of 253 families indicates that sagittal synostosis is transmitted as a dominant disorder with 38% penetrance and 72% of sporadic cases. The frequency of twinning was 4.8% with only 1 concordance for sagittal synostosis in a monozygotic twin pair. The possibility of a mechanical pathogenesis in sporadic cases is discussed.

Adolescent↗

Possible genetic heterogeneity in the Saethre-Chotzen syndrome.

Saethre-Chotzen syndrome is an autosomal dominant acrocephalosyndactyly syndrome whose gene has been assigned to chromosome 7p. Cytogenetic and linkage analyses have enabled the interval encompassing the disease gene to be delimited to a short region of chromosome 7p15.3-p21.2. Based on the genetic analysis of three unreported families, we confirm the location of the disease gene(s) in the interval defined by loci D7S664 and D7S493 (Zmax = 4.78 at [symbol: see text] = 0 at the D7S488 locus) but fail to decide whether one or more disease-causing genes map in this genetic interval.

Acrocephalosyndactylia↗

Genetic study of nonsyndromic coronal craniosynostosis.

From a series of 1265 individuals with different craniosynostoses hospitalized between 1976 and 1993, 260 probands with nonsyndromic unilateral (181) or bilateral (79) coronal synostosis were analysed. The prevalence of craniosynostoses was estimated as 1 in 2100 children. In the group of coronal synostosis, family history was obtained on 192 probands in 180 pedigrees. The male:female ratio was 1:2. The average paternal age was 32.7 +/- 6.4 years, which is significantly higher than normal. In 26 of the 180 pedigrees, a high degree of familial aggregation was observed, giving a 14.4% figure of familial cases. The bicoronal synostoses were significantly more often familial than the unicoronal synostoses. Segregation analysis of these families leads to the conclusion that coronal synostosis is transmitted as a dominant disorder with 0.60 penetrance and 61% of sporadic cases.

Adult↗

No evidence of genetic heterogeneity in Crouzon craniofacial dysostosis.

Crouzon craniofacial dysostosis (CFD) is an autosomal dominant form of craniosynostosis characterized by an abnormal skull shape, with hypertelorism, prominent eyes and midfacial retrusion. Recently, a gene for CFD has been mapped to chromosome 10q25-q26 and mutations in exon B of the fibroblast growth factor receptor 2 (FGFR2) gene have been identified. Here, we report the mapping of a CFD gene to chromosome 10q by close linkage to probe AFMa197wb1 at locus D10 S1483 in six unrelated families of French ancestry (Zmax = 4.69 at theta = 0) and provide additional evidence of genetic homogeneity of this condition. In addition, we report a novel mutation in exon B of the FGFR2 gene (Cys 342 Trp) in familial CFD and describe recurrent mutations at codon 342 as a particularly frequent event in CFD. Since mutations in the extracellular domain of the FGFR2 gene are observed in a few clinically distinct craniosynostosis syndromes (CFD, Jackson-Weiss, Apert and Pfeiffer), the present study gives support to the variable clinical expression of FGFR2 mutations in humans.

Chromosome Mapping↗

Glycoprotein hormone alpha-subunit secretion in prolactinomas and in non-functioning adenomas: relation with the tumour size.

OBJECTIVE: Free glycoprotein hormone alpha-subunit plasma levels have been reported to be increased in glycoprotein hormone-secreting adenomas and in acromegaly, but rarely in prolactinomas and in only two cases of Cushing's disease. The prevalence of elevated plasma alpha-subunit levels in patients with non-functioning adenomas is still unclear. In addition, no previous work has described plasma alpha-subunit levels in a comprehensive series of adenomas characterized by in-vivo secretion and/or immunocytochemistry. PATIENTS: Thirty-seven patients with definite prolactinomas and 48 with non-functioning tumours characterized by immunocytochemistry were studied, from a series of 145 consecutive patients including 33 acromegalics, 18 patients with glycoprotein hormone-secreting adenomas and 9 with Cushing's disease. MEASUREMENTS: Plasma free alpha-subunit was measured by radioimmunoassay in all patients and in a large sample of normal subjects to establish normal ranges according to sex, age and menstrual status. Tumour volume index was the product in cm3 of length, width and height of the adenoma as assessed by computerized tomography or magnetic resonance imaging. RESULTS: Twelve of the 37 (32%) patients with prolactinomas had increased plasma alpha-subunit levels; their tumours were significantly larger with significantly higher plasma PRL levels than those of patients without increased plasma alpha-subunit levels (P < 0.02). All prolactinomas above 50 cm3 were associated with alpha-subunit secretion, whereas only 6 of 29 smaller tumours were similarly associated. Twelve of the 48 'non-functioning' adenomas actually secreted alpha-subunit in vivo: 8 gonadotrophin-secreting, 2 'pure' alpha-secreting, one with negative immunocytochemistry and one necrotic adenoma. Their volumes were significantly higher than those of adenomas without increased plasma alpha-subunit levels (P < 0.04). Plasma alpha-subunit levels were increased in the 6 patients with TSH-secreting adenomas, 8 of 12 with FSH-secreting adenomas, 11 of 33 acromegalics and none of those with Cushing's disease. CONCLUSION: Plasma free alpha-subunit levels were increased in 49 of 145 patients (34%). For prolactinomas and 'non-functioning' adenomas, alpha-subunit hypersecretion was seen more often with larger tumours. Half of the cases with increased free alpha-subunit in this series were patients harbouring an adenoma which did not stain for an intact glycoprotein hormone.

Adenoma↗

Triiodothyronine therapy in open-heart surgery: from hope to disappointment.

A controversy persists as to whether cardiopulmonary bypass (CPB) decreases plasma levels of triiodothyronine (T3), thereby justifying peri-operative administration of T3 to improve haemodynamic recovery. To examine the effects of T3 therapy on post-CPB haemodynamics and to determine whether the potential inotropic effects of T3 are mediated by an increase in beta-adrenergic responsiveness, a prospective, randomized, double-blind, placebo-controlled study was performed in 20 patients undergoing cardiac surgery with CPB. T3 or placebo solution (10 patients in each group) was given intravenously at the time of aortic unclamping and 4, 8, 12 and 20 h thereafter. End points included (1) thyroid hormone levels measured by radioimmunoassay (2) standard haemodynamic parameters (3) the density of lymphocyte beta-adrenoceptors measured by a radioligand (125I-iodocyanopindolol) binding technique. Post-CPB values (cross clamp removal) of T3 (pg.ml-1) were not significantly decreased compared with pre-CPB values: 3.3 +/- 0.2 vs 3.1 +/- 0.2 in controls and 3.3 +/- 0.4 vs 3.7 +/- 0.6 in T3-treated patients, respectively. The haemodynamic parameters were no different between the two groups at any postoperative time point. Likewise, density and affinity of lymphocyte beta-adrenoceptors were not significantly different from pre-operative values in either group. Thus, there seems to be no sound justification for a routine use of T3 in patients undergoing open-heart procedures.

Adult↗

Shrinkage of a primary thyrotropin-secreting pituitary adenoma treated with the long-acting somatostatin analogue octreotide (SMS 201-995).

The long-acting somatostatin agonist octreotide can control TSH hypersecretion from most thyrotropic adenomas. Octreotide therapy has even been shown to improve chiasmal dysfunction. We report another patient in whom octreotide therapy was associated with gradual suppression of TSH hypersecretion, which escaped partially, dramatic and very rapid and sustained improvement of chiasm compression, and dramatic and sustained shrinkage of an unresectable TSH-secreting pituitary tumour. Unusual and prolonged gastrointestinal adverse reactions eventually disappeared except for steatorrhea. In conclusion, octreotide may be considered as first line treatment in patients with unresectable thyrotropic adenomas.

Adenoma↗

[Biological detection of hormonal overdose in treated peripheral thyroid insufficiency. Comparison of ultrasensitive TSH and the TRH tests. Therapeutic consequences].

Fifty-two patients with peripheral hypothyroidism receiving hormone replacement therapy at conventional dosages and having normal free thyroid hormone levels underwent a TRH test (200 micrograms). This test was found areactive (delta TSH less than 4.0 microU/ml) indicating therapeutic overdosage in 38 cases (73 p. 100). It was possible to reestablish reactivity to the TRH test in 20 of these patients by progressively reducing the dosage to an average of 70 p. 100 of the initial dose. This reduction had no effects on body weight, heart rate or serum lipids. These results show that the plasma concentrations of thyroid hormones are poor indicators of overdose and underline the limitations of the concept of group normality to which that of individual normality is to be preferred. The treatment of hypothyroidism is much easier to adapt using the TSH test. Since the introduction of ultrasensitive methods of assaying this hormone the value of the TRH test has been questioned. We have defined the limits beyond which the TRH test is of no value and the basal TSH dosage adequate. There remains a zone (basal TSH between 0.15 and 1.00 microU/ml in our laboratory) within which the result of the TRH test cannot automatically be deduced from that of the basal TSH.

Adult↗

[Thyrotropic function in patients with a hypothalamic or pituitary tumor. Possibility of the secretion of a TSH with reduced biological activity].

Thyrotropic function was studied in 100 patients with hypothalamic or pituitary tumours before treatment. Eighteen patients with thyroid deficiency showed no signs of primary hypothyroidism. This was also showed in 4 other hypothyroid patients who had pituitary tumours studied later on. Only 4 of these 22 patients had TSH deficiency. The other 18 had normal or high plasma TSH levels, and the TSH response to TRH was normal but often delayed and/or prolonged. This pattern, suggestive of secretion of TSH with reduced biological activity, might however be due to other factors. Tumoral invasion of the hypothalamus, present in these 18 cases, could reduce secretion of TRH and dopamine. Hypothyroidism would then be secondary to TRH deficiency if TRH is considered to have a direct thyroid-stimulating action, and, like dopamine deficiency, could contribute to maintaining normal or high TSH secretion.

Adenoma↗