PubMed Health⌕ Search

Biomedical subjects

D Bonneau

Publications and source records attributed to D Bonneau.

At least 37 records · Page 2Linked to original sources

Prenatal diagnosis of Gaucher's disease type 2. Ultrasonographic, biochemical and histological aspects.

We report on the early prenatal diagnosis of fetal Gaucher disease type 2 by ultrasound examination and beta-glucosidase activity assay on amniocytes from a fetus of 15 weeks' gestation whose first sibling fetus had previously been affected with hydrops fetalis. These cases emphasize the importance of the pathological examination of all fetuses presenting with hydrops fetalis and also stress that minimal and precocious echographic signs can be suggestive of such a lysosomal storage disease.

Adult↗

Mutations of the human PTEN gene.

PTEN (phosphatase and tensin homolog deleted on chromosome ten), a recently discovered tumor suppressor gene, appears to negatively control the phosphoinositide 3-kinase signaling pathway for regulation of cell proliferation and cell survival by dephosphorylating the phosphatidylinositol 3,4,5-triphosphate. To date, 110 germline PTEN mutations have been reported in patients affected with two tumor predisposing syndromes, each having overlapping clinical features: Cowden disease and Bannayan-Riley-Ruvalcaba syndrome. These germline mutations are scattered along the length of the gene, with the exception of exon 9 (no mutation reported) and exon 1 (only two mutations reported). A mutational hot spot is found in exon 5, which encodes the phosphatase catalytic core motif, and recurrent mutations are also found at CpG dinucleotides suggesting deamination-induced mutations. PTEN has also been found to be defective in a large number of sporadic human tumors. In this article, 332 somatic point mutations of PTEN, occurring in primary tumors or metastasis, have been reviewed. Somatic PTEN mutations are more particularly involved in two types of human cancers: endometrial carcinomas and glioblastomas. In most cases, these somatic mutations result in protein inactivation and, as with germline mutations, recurrent somatic mutations are found in CpG dinucleotides. A mutagenesis by insertion-deletion in repetitive elements is however specifically observed in endometrial carcinomas.

Abnormalities, Multiple↗

W syndrome: report of three cases and review.

Only three cases of W syndrome have been reported. These patients have a typical "pugilistic" face, incomplete oral cleft, absent upper incisors, mental retardation, spasticity, seizures, and acne scars. Two of them had additional skeletal anomalies. Here we report on three male patients with findings compatible with the W syndrome. We emphasize the importance of some constant findings and describe additional signs. Familial history supports X-linked dominant heredity, as postulated previously.

Abnormalities, Multiple↗

Splenogonadal fusion limb defect syndrome: report of five new cases and review.

Splenogonadal fusion (SGF) is a rare congenital malformation in which the spleen is abnormally connected to the gonad. SGF may occur as an isolated condition or may be associated with other malformations, especially with terminal limb defects in what is called splenogonadal fusion limb defect (SGFLD) syndrome. In this article, we report on 5 new cases of SGFLD and we review the 25 cases reported since 1889. Most cases reviewed here have a combination of severe limb and oro-mandibular defects, suggesting that SGFLD may be related to the broader group of Hanhart complex. In addition, several cases have limb malformations and facial anomalies, which suggest that SGFLD overlaps with both femur-fibula-ulna dysostosis and femoral-facial syndrome. The hypothesis of a vascular disruptive event, occurring between the 5th and the 7th weeks of gestation, could explain the limb defects, the mandibular hypoplasia, and the fusion of the spleen to the gonad observed in SGFLD. However, this heterogenous and polytopic condition could also be the consequence of a primary field defect. All the cases to date reported have been sporadic and the recurrence risk is probably low. However, a recent case of Roberts syndrome with SGF was reported that suggests careful examination of chromosomal status.

Abnormalities, Multiple↗

Heterotaxy-neural tube defect and holoprosencephaly occuring independently in two sib fetuses.

We report on two sib fetuses, products of a consanguineous union, who had multiple and apparently unrelated malformations. The first fetus, a female, had trilobed lungs, a single cardiac ventricle, asplenia, situs ambiguus of the liver, and a lumbosacral meningomyelocele. The brain of this fetus was normal. The second fetus, a male, had bilobed lungs, a single cardiac ventricle, situs solitus of the abdominal organs and spleen, and a semilobar holoprosencephaly. The occurrence of these malformations in sibs of different sexes and the parental consanguinity suggest a recessive mutation in a gene responsible for both heterotaxy and midline defects, including holoprosencephaly.

Female↗

Histology of familial thyroid tumours linked to a gene mapping to chromosome 19p13.2.

This paper describes the pathology of thyroid tumours showing an autosomal mode of inheritance linked to a gene that maps to chromosome 19p13.2. All the affected members from the family (seven males and two females; mean age 23 years) were clinically euthyroid and presented with nodular goitre; tumour recurrence after thyroidectomy was observed in four. In four of the five patients studied, the tumours were multifocal, bilateral well demarcated or encapsulated and composed of follicles, papillae, trabeculae/solid areas (often resembling hyalinizing trabecular adenoma of the thyroid) or an admixture, formed by cells with pale to intense cytoplasmic eosinophilia. A diagnosis of multiple adenomatous goitre was made in the thyroidectomy specimen from two patients, while the other two patients showed, in addition to multiple adenomas, a co-existent oxyphil papillary carcinoma. The fifth patient had an oxyphil cell carcinoma. All tumours were of follicular cell origin as shown by immunocytochemistry. Less than a third of the benign tumours and all three carcinomas showed a variable number of neoplastic cells diffusely immunostained for mitochondria. Histological findings of a 'multiple adenomatous goitre', non-endemic 'multinodular goitre' or multiple neoplasms of follicular cell origin with the morphology of those described here, particularly in young patients, should alert the pathologist and physician to the possibility of an inherited trait, with its implications for family screening. The tumours are usually benign and well demarcated but because of multicentricity and consequently increased risk of recurrence and/or progression to carcinoma, total thyroidectomy should be advocated.

Adenoma↗

Thyroid pathologic findings in patients with Cowden disease.

We describe the histologic findings in thyroid glands from six female and five male patients with Cowden disease. The patients were aged 9 to 43 years (mean age, 26 years). The salient thyroid lesions in this syndrome were multicentric follicular adenomas and adenomatous (parenchymatous, hyperplastic) nodules showing a wide range of nonspecific cytoarchitectural patterns. Multiple tiny cellular foci, so-called microadenomas, were also a feature. Specific lesions composed of oxyphil or clear cells, a tumor with features of hyalinizing trabecular adenoma, and an adenolipoma also occurred. Two cases showed a follicular carcinoma in addition to multiple benign follicular cell proliferations. The follicular carcinomas occurred at an older age and were larger in size than the clinically significant benign nodular lesions, suggesting tumor progression. All tumors showed thyroglobulin immunoreactivity and were negative for calcitonin. The histologic findings of a multiple adenomatous goiter or multiple follicular adenomas, particularly in children and young adults, should alert the pathologist and physician to the possibility of an inherited trait, such as Cowden disease, with its implications for family screening. The tumors are usually benign and well demarcated, but, because of multicentricity and increased risk of recurrence or progression to carcinoma, total thyroidectomy should be advocated.

Adenocarcinoma, Follicular↗

Mapping of a gene predisposing to familial thyroid tumors with cell oxyphilia to chromosome 19 and exclusion of JUN B as a candidate gene.

BACKGROUND: Familial nonmedullary thyroid carcinoma (FNMTC) is a clinical entity characterized by a more aggressive phenotype than the sporadic counterpart. The transmission of susceptibility of FNMTC is compatible with autosomal dominant inheritance. We report the identification of a new entity of FNMTC and the mapping of the responsible gene named TCO (for thyroid tumor with cell oxyphilia). METHODS: In one family, multinodular goiters were diagnosed in six individuals and papillary thyroid carcinoma was diagnosed in three. Eight patients were operated on. Blood samples were collected from the nine affected patients and from eight unaffected relatives. The gene was mapped by linkage analysis with a whole-genome panel of microsatellite markers. RESULTS: The neoplastic cells from all lesions showed characteristic faint to marked cytoplasmic oxyphilia. We found a logarithm of odd ratio (LOD) score of 2.41 at theta = 0 for marker D19S586. Additional markers were typed in the region and were found to be in linkage, with LOD scores peaking at markers D19S916 (Zmax = 3.01 at theta = 0) and D19S413 (Zmax = 2.95 at theta = 0). All these markers have been physically mapped to 19p13.2. CONCLUSIONS: TCO was mapped to chromosome 19p13.2. Interestingly, both the benign and malignant thyroid tumors in this family exhibit some degree of oxyphilia, which has not been described until now in the familial forms of NMTC.

Adenoma, Oxyphilic↗

A gene predisposing to familial thyroid tumors with cell oxyphilia maps to chromosome 19p13.2.

Familial nonmedullary thyroid cancer (FNMTC) is a clinical entity characterized by a phenotype more aggressive than that of its sporadic counterpart. Families with recurrence of nonmedullary thyroid cancer (NMTC) have been repeatedly reported in the literature, and epidemiological data show a very high relative risk for first-degree relatives of probands with thyroid cancer. The transmission of susceptibility to FNMTC is compatible with autosomal dominant inheritance with reduced penetrance, or with complex inheritance. Cases of benign thyroid disease are often found in FNMTC kindreds. We report both the identification of a new entity of FNMTC and the mapping of the responsible gene, named "TCO" (thyroid tumors with cell oxyphilia), in a French pedigree with multiple cases of multinodular goiter and NMTC. TCO was mapped to chromosome 19p13.2 by linkage analysis with a whole-genome panel of microsatellite markers. Interestingly, both the benign and malignant thyroid tumors in this family exhibit some extent of cell oxyphilia, which, until now, had not been described in the FNMTC. These findings suggest that the relatives of patients affected with sporadic NMTC with cell oxyphilia should be carefully investigated.

Adenoma, Oxyphilic↗

Mutations of PTEN in patients with Bannayan-Riley-Ruvalcaba phenotype.

We report three new mutations in PTEN, the gene responsible for Cowden disease in five patients with Bannayan-Riley-Ruvalcaba syndrome from three unrelated families. This finding confirms that Cowden disease, a dominant cancer predisposing syndrome, and Bannayan-Riley-Ruvalcaba syndrome, which includes macrocephaly, multiple lipomas, intestinal hamartomatous polyps, vascular malformations, and pigmented macules of the penis, are allelic disorders at the PTEN locus on chromosome 10q.

Adolescent↗

[Tissue expression of a gene potentially implicated in some diseases with retinal and renal involvement].

We have produced a monoclonal antibody (HA34) that specifically reveals the pigmented epithelium in the eye and the proximal convoluted tubules of the kidney, whatever the developmental stage. The results obtained with the kidney of other mammals suggest that the antigen is human specific. Its molecular weight is approximately 200 kDa. The epitope recognized by HA34 is always present on cell lines grown in vitro. This allowed us to use somatic cell interspecific hybrids to localize the gene implicated in the cytogenetic band 11q13, between microsatellites D11S1777 (AFMa046wa9) and D11S913 (AFM164zf12) in a 9 cM space. This region is involved in forms of retinitis pigmentosa, some of which can also include kidney abnormalities. We propose that this gene is possibly implicated in some of these diseases.

Animals↗

Administration of a GABAB agonist baclofen before running to exhaustion in the rat: effects on performance and on some indicators of fatigue.

The present study was designed to examine the effects of administration of a GABAergic agonist (Baclofen) on run-time to exhaustion in trained and untrained rats, and on some indicators of fatigue. Run-time to exhaustion on a treadmill set at a speed of 25 m.min-1 was significantly increased in both untrained (p < 0.01) and trained rats (p < 0.005) administered with baclofen one hour before the exercise. The animals who had run the longest time displayed the lowest concentrations of liver and muscle glycogen, and a decrease in plasma glucose concentrations (p < 0.05). The results of this investigation suggest that fatigue during prolonged exercise can be influenced by pharmacological administration of a GABAergic agonist. Indicators of fatigue such as glycemia, liver and muscular glycogen are not the limiting factors of performance and central mechanisms play a key role at exhaustion.

Analysis of Variance↗

Abnormal cholesterol biosynthesis in the Smith-Lemli-Opitz and the lethal acrodysgenital syndromes.

UNLABELLED: The Smith-Lemli-Opitz syndrome (SLO) is an autosomal recessive disorder characterized by dysmorphic facial features with abnormal limbs and genitalia. Two forms have been recognized based on clinical course and severity: the classical SLO (type I) and the lethal acrodysgenital syndrome (type II). Type I SLO has been recently ascribed to a defect in cholesterol synthesis. Taking advantage of a series of seven patients including five type I and two type II SLO, we describe micrognathia, severe microcephaly, major ante and post natal growth retardation and feeding difficulties as consistent features in the disease. In addition, we give support to the presence of abnormal cholesterol levels in the lethal acrodysgenital syndrome but find no correlation between plasma sterol levels and the clinical severity of the disease. CONCLUSION: The identification of the same biochemical defect in both types of Smith-Lemli-Opitz Syndrome suggests that despite major discrepancies in clinical course and severity, type I and type II SLo are probably allelic disorders.

Child↗

Increased paternal age in CHARGE association.

The acronym CHARGE refers to a non-random clustering of congenital malformations whose cause remains unknown. Here, we report on a series of 41 patients and find a significant increase in mean paternal age of birth of CHARGE patients (33.7 +/- 8 years) compared with the control population (30.8 +/- 5 years). In contrast, maternal age was not statistically different in patients and controls. These data suggest the possible role of a dominant mutation or, less likely, a subtle chromosomal abnormality in CHARGE association.

Abnormalities, Multiple↗

Evidence for a fourth locus in Usher syndrome type I.

Usher syndrome type I (US1) is an autosomal recessive condition in which three different genes have been already localised (USH1A, USH1B, and USH1C on chromosomes 14q32, 11q13, and 11p15 respectively). The genetic heterogeneity of US1 has been confirmed in a previous study by linkage analysis of 20 French pedigrees. Here, we report the genetic exclusion of the three previously reported loci in two large multiplex families of Moroccan and Pakistani origin, suggesting the existence of at least a fourth locus in Usher syndrome type I.

Abnormalities, Multiple↗