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C Blanchet-Bardon

Publications and source records attributed to C Blanchet-Bardon.

At least 55 records · Page 3Linked to original sources
PubMed1992

Prenatal diagnosis in a subset of trichothiodystrophy patients defective in DNA repair.

Trichothiodystrophy (TTD) is an autosomal recessive disorder characterized by brittle hair with reduced sulphur content, and mental and physical retardation. Numerous additional clinical features may be present, producing a very heterogeneous syndrome. Many cases exhibit ichthyosis and photosensitivity. Cells from photosensitive TTD patients show reduced DNA repair levels similar to those found in xeroderma pigmentosum. TTD patients have a short life expectancy, and no treatment is known or envisaged. We report the prenatal diagnosis of TTD in two French families, based on DNA repair measurements in trophoblasts or amniotic cells, with later confirmation by microscopic analysis of the fetal hairs. Although the DNA repair defect was less marked in the fetal cells when compared with fibroblasts from the index case, measurement of DNA repair by unscheduled DNA synthesis provided unambiguous evidence of defective DNA repair in the fetal cells. This method is therefore a suitable prenatal diagnostic test for those TTD families in which a DNA repair defect has been identified.

Adult↗
PubMed1992

Keratosis follicularis spinulosa decalvans: report of a case with ultrastructural study and unsuccessful trial of retinoids.

Keratosis follicularis spinulosa decalvans (KFSD) is a genetic disorder characterized by disseminated follicular hyperkeratosis, especially localizated to scalp and face. We report the case of a new patient displaying typical features of KFSD. Ultrastructural study was performed and displayed round keratohyalin granules in follicular keratinocytes. Trial with etretinate, which has not been reported before in this disease, proved to be ineffective.

Biopsy↗
PubMed1992

Genetic linkage of recessive dystrophic epidermolysis bullosa to the type VII collagen gene.

Generalized mutilating recessive dystrophic epidermolysis bullosa (RDEB) is characterized by extreme skin fragility owing to loss of dermal-epidermal adherence. Immunohistochemical studies have implicated type VII collagen, the major component of anchoring fibrils, in the etiology of RDEB. In this study, we demonstrate genetic linkage of the type VII collagen gene and the generalized mutilating RDEB phenotype. We first identified a Pvull polymorphic site by digestion of an amplified product of the type VII collagen gene, which was shown to reside within the coding region. Genetic linkage analysis between this marker and the RDEB phenotype in 19 affected families which were informative for this polymorphism showed no recombination events, and gave a maximum lod score of 3.97 at a recombination fraction (theta) of 0, demonstrating that this DNA region is involved in this form of RDEB. These data provide strong evidence that the type VII collagen gene, which has also been linked with the dominant form of the disease, harbors the mutation(s) causing the generalized mutilating form of RDEB in these families, thus underscoring the major functional importance of type VII collagen in basement membrane zone stability.

Base Sequence↗
PubMed1991

Acitretin in the treatment of severe disorders of keratinization. Results of an open study.

The purpose of this open, noncomparative study with acitretin (Ro 10-1670) was to evaluate the clinical response of patients with various nonpsoriatic disorders of keratinization and to establish for these patients the optimal dosage for both efficacy and tolerance. Thirty-three patients (21 adults and 12 children or adolescents) with ichthyoses, palmoplantar hyperkeratosis, or Darier's disease were treated for a period of 4 months. Most patients showed marked improvement or remission. The results obtained in congenital ichthyosiform erythroderma, lamellar ichthyosis, and Papillon-Lefèvre syndrome were judged as better than those usually reported with etretinate. The side effects observed in our patients were similar to those reported with etretinate, with the exception of scaling of palms and soles, which had an incidence and severity greater than expected with etretinate. The optimal acitretin dosage providing the best efficacy with minimal undesirable effects varied from patient to patient. The mean daily dose (+/- SD) was 27 +/- 11 mg in adults and 0.7 +/- 0.2 mg/kg in children or adolescents.

Acitretin↗
PubMed1991

Exclusion of linkage between the collagenase gene and generalized recessive dystrophic epidermolysis bullosa phenotype.

Generalized recessive dystrophic epidermolysis bullosa (RDEB) is a severe inherited autosomal disease characterized by dermolytic blister formation. Enhanced collagenase and/or abnormal collagenase have been reported in skin from affected patients, suggesting that collagenase could be responsible for the absence of anchoring fibrils in this disorder. We used a genetic linkage approach to test the hypothesis that this disease is due to a defect in the collagenase gene in nine affected families. Analysis of amplified genomic DNA fragments of the collagenase gene by means of denaturing gradient gel electrophoresis (DGGE) allowed us to detect intragenic polymorphisms, which were subsequently characterized by direct genomic sequencing. Segregation analysis of these polymorphic sites showed exclusion of linkage between the collagenase gene and generalized RDEB phenotype in a family with consanguineous parents and three affected children. However, the possibility of linkage with the collagenase gene in the other eight families tested could not be excluded. The genetic markers described here provide a tool for investigating genetic linkage in other affected families. Overall, our results show that generalized RDEB can be caused by a defect in a gene other than the collagenase gene, and support the hypothesis that the genetic defect lies in abnormal anchoring fibril formation.

Base Sequence↗
PubMed1991

Monoclonal antibody GB3 defines a widespread defect of several basement membranes and a keratinocyte dysfunction in patients with lethal junctional epidermolysis bullosa.

An antigen expressed at the dermal-epidermal junction as well as in some other human basement membranes (BM) has been detected by the use of a monoclonal antibody termed GB3. This antigen, synthesized by cultured normal human keratinocytes, has been identified as a 600-kilodalton glycoprotein different from other known components of BM. Using indirect immunofluorescence, GB3 was found to be not reactive with the epidermal BM in patients with lethal junctional epidermolysis bullosa. The present study demonstrates (by indirect immunofluorescence) that GB3 defines a widespread defect of several BM in these patients. Furthermore, it gives evidences for an intrinsic biologic defect of lethal junctional epidermolysis bullosa epidermal keratinocytes using in vitro culture of these cells. Whether the lack of GB3 reactivity is the consequence of a true absence of the antigen or an alteration of its molecular structure is not yet known. Nevertheless, GB3 is a useful probe for both rapid and prenatal diagnosis of lethal junctional epidermolysis bullosa, which will give new insights into the molecular comprehension of this disorder.

Antibodies, Monoclonal↗
PubMed1990

Familial occurrence of KID (keratitis, ichthyosis, deafness) syndrome. Case reports of a mother and daughter.

Keratitis, ichthyosis, and deafness (KID) syndrome in a mother and her daughter is reported. Both patients showed the typical cutaneous abnormality of papillomatous hyperkeratosis, which gave the skin a grainy, rugose, spiculated appearance, together with keratitis with corneal neovascularization and a neurosensory hearing defect. Treatment with etretinate did not benefit the daughter. The mother had marked keratitis with progressive corneal opacification that required repeated bilateral corneal grafts, which were unsuccessful. This is the second report of hereditary transmission of this disorder. An autosomal dominant mode of inheritance is probable.

Adult↗
PubMed1990

A case of cicatricial pemphigoid with circulating IgA and IgG antibodies directed against 280 kD, 165 kD and 120-130 kD epidermal antigens.

A case of subepidermal autoimmune blistering disease in an 86-year-old woman is reported. Clinical features were those of a cicatricial pemphigoid, with prominent mucosal involvement leading to conjunctival and nasal scarring. Direct immunofluorescence findings were consistent with either cicatricial pemphigoid or linear IgA dermatosis, since both IgG and IgA linear deposits were found at the basal membrane zone. Immunoelectron microscopy of perilesional skin revealed IgA deposits within the lamina lucida and immunoblotting of the patient's serum disclosed IgA and IgG antibodies directed against epidermal antigens of 280, 165 and 120-130 kD.

Aged↗