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G Tadini

Publications and source records attributed to G Tadini.

At least 37 records · Page 2Linked to original sources
PubMed1996

Defective integrin alpha 6 beta 4 expression in the skin of patients with junctional epidermolysis bullosa and pyloric atresia.

Junctional epidermolysis bullosa (JEB) is a heterogeneous group of rare inherited skin disorders in which defects in cell adhesion components cause incomplete formation of hemidesmosomes. We have immunohistochemically examined the skin from ten JEB patients (JEB gravis, n = 4; JEB mitis, n = 3; JEB plus pyloric atresia [JEB/PA], n = 3) using monoclonal antibodies specific for the integrin adhesion receptors alpha 3 beta 1 and alpha 6 beta 4, and for the alpha 3, beta 3, and gamma 2 subunits of the basement membrane ligand, laminin 5. Consistent with our previous reports, only the JEB gravis patients without associated pyloric atresia expressed reduced or absent epitopes for laminin-5 subunits in their epidermal basement membrane. In contrast, all three JEB/PA cases showed abnormalities in integrin alpha 6 beta 4, but not in laminin 5, expression in their basal epidermal cells. Integrin beta 4 subunit was undetectable in the biopsied epidermis of these JEB/PA individuals using five different monoclonal antibodies that recognize both intra- and extracellular epitopes. The absence of the beta 4 subunit in the epidermis of JEB/PA specimens was confirmed by Western blot analysis of tissue extracts. Epidermal expression of the integrin alpha 6 subunit was variable in the JEB/PA patients. Abnormal integrin alpha 6 beta 4 expression may define the subset of JEB cases with pyloric atresia. These results strongly implicate a functional role for alpha 6 beta 4 in the formation of complete hemidesmosomes and in stable adhesion of basal keratinocytes to the basement membrane in vivo.

Adult↗
PubMed1995

Altered expression of a new antigen of the dermal-epidermal junction (NU-T2 DEJ Ag) in junctional epidermolysis bullosa.

NU-T2 antigen (Ag) is a new and recently described antigen of the dermal-epidermal junction, recognized by an anti-CD1b monoclonal antibody denominated NU-T2. We studied NU-T2 Ag expression in junctional epidermolysis bullosa (13 patients) and in other forms of hereditary epidermolysis bullosa (23 patients), comparing the results with nicein expression. In junctional epidermolysis bullosa gravis type no differences were found between the expression of NU-T2 and nicein, both being negative in bullous as well as in non-bullous skin. Interestingly, in mitis type junctional epidermolysis bullosa, NU-T2 Ag was found to be absent or reduced in five of six patients both in lesional and in uncleaved skin. When compared with nicein expression, clearcut differences were found, further suggesting that these two antigens are different. These data confirm that NU-T2 Ag is a novel epitope of the dermal-epidermal junction, probably relevant in dermal-epidermal cohesion, and it could be responsible, together with nicein, 19-DEJ-1 and other adhesion molecules, for the different subtypes of junctional epidermolysis bullosa. Finally, NU-T2 monoclonal antibody is a new relevant tool for the diagnosis, classification, and prenatal diagnosis of junctional epidermolysis bullosa.

Antigens↗
PubMed1994

Genetic and clinical mosaicism in a type of epidermal nevus.

BACKGROUND: Many skin disorders are characterized by a mosaic pattern, often with alternating stripes of affected and unaffected skin that follow the lines of Blaschko. These nonrandom patterns may be caused by a postzygotic mutation during embryogenesis. We studied the genetic basis of one such disorder, epidermal nevus of the epidermolytic hyperkeratotic type. Epidermolytic hyperkeratosis is an autosomal dominant blistering skin disease arising from mutations in the genes for keratin (K) 1 and 10. The offspring of patients with epidermal nevi may have generalized epidermolytic hyperkeratosis. METHODS: We studied the K1 and K10 genes in blood and in the keratinocytes and fibroblasts of lesional and nonlesional skin from three patients with epidermal nevi and four of their offspring with epidermolytic hyperkeratosis. RESULTS: In the patients with epidermal nevi, point mutations in 50 percent of the K10 alleles of epidermal cells were found in keratinocytes from lesional skin; no mutations were detected in normal skin. This mutation was absent or underrepresented in blood and skin fibroblasts. In the offspring with epidermolytic hyperkeratosis, the same mutations as those in the parents were found in 50 percent of the K10 alleles from all cell types examined. CONCLUSIONS: Epidermal nevus of the epidermolytic hyperkeratotic type is a mosaic genetic disorder of suprabasal keratin. The correlation of mutations in the K10 gene with lesional skin and the correlation of the normal gene with normal skin provide evidence that genetic mosaicism can cause clinical mosaicism.

Alleles↗
PubMed1994

Pityriasis rotunda: report of a familial occurrence and review of the literature.

Pityriasis rotunda is an uncommon dermatosis characterized by multiple, widely distributed, strikingly circular hypopigmented or hyperpigmented patches that are slightly scaly. It has been described in Oriental and black patients, usually in association with certain infective or malignant systemic diseases. Pityriasis rotunda is rare in white patients and does not act as a marker of malignancy. Our ultrastructural and histologic findings demonstrated that pityriasis rotunda is more closely related to congenital ichthyoses than ichthyosis vulgaris, contrary to previous reports. On the basis of our studies and a review of the literature, it seems that two types of pityriasis rotunda exist with significant prognostic differences.

Adult↗
PubMed1994

Rapp-Hodgkin syndrome and AEC syndrome: are they the same entity?

Rapp-Hodgkin syndrome and AEC syndrome are two disorders in which ectodermal dysplasia and clefting are associated. Rapp-Hodgkin syndrome is an autosomal dominant condition characterized by cleft lip and palate, peculiar craniofacial features, and ectodermal dysplasia, consisting of abnormalities of teeth, hair, nails and sweating. AEC syndrome manifests the same defects plus ankyloblepharon and a higher frequency of scalp dermatitis. A child affected by ectodermal dysplasia associated with clefting, ankyloblepharon, severe scalp dermatitis, and the characteristic Rapp-Hodgkin facies is reported. The overlap between Rapp-Hodgkin syndrome and AEC syndrome is discussed. Critical review of both disorders suggest that AEC syndrome and Rapp-Hodgkin syndrome represent the same entity.

Cleft Palate↗
PubMed1994

A case of congenital reticular ichthyosiform erythroderma--ichthyosis 'en confettis'.

We describe the third case of congenital reticular ichthyosiform erythroderma (CRIE), a rare inherited keratinization disorder, the second with the peculiar reticulate skin pattern. The same case had been previously described and defined, for the clinical appearance, as ichthyosis 'en confettis'. An 18-year-old girl was born with the clinical features of an erythrodermic lamellar ichthyosis. Patches of normal skin enclosed by erythematous-ichthyotic skin in a reticular arrangement appeared on the trunk at the age of 10 years, and they enlarged slowly during 6 years. The treatment with etretinate, started 2 years ago, further increased this process. Another peculiar clinical feature is a remarkable hypertrichosis. At the ultrastructural level, perinuclear deposits of filamentous material in vacuolized keratinocytes of the upper epidermis, pathognomonic for CRIE, were demonstrated. This suggests that CRIE and ichthyosis 'en confettis' are the same disorder. In addition the peculiar clinical presentation of this rare genodermatosis develops only during late childhood and puberty. The identification of three sporadic cases only leaves the problem of inheritance still unsolved.

Adolescent↗
PubMed1993

Prenatal testing in a fetus at risk for autosomal dominant polycystic kidney disease and autosomal recessive junctional epidermolysis bullosa with pyloric atresia.

Amniocentesis and fetal skin biopsies were performed at 18 weeks of gestation in a fetus at risk for autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive junctional epidermolysis bullosa (EBJ) with pyloric atresia. A previous son of the couple under investigation had died at 3 months of EBJ. The mother of the propositus has ADPKD. Genetic linkage studies were carried out in 11 relatives (4 with ADPKD), and on fetal DNA obtained from cultured amniocytes, using 8 flanking DNA markers tightly linked to the PKD1 locus on chromosome 16p, and a DNA marker linked to another putative ADPKD locus on chromosome 2p. The linkage results indicated that the fetus had not inherited the ADPKD chromosome from the affected mother, with a diagnostic accuracy of > 99%. Ultrastructural and immunohistochemical analyses of multiple fetal skin biopsies showed no EBJ-associated abnormalities. Thus, combining recent morphological and molecular diagnostic methods, we could show that the fetus was free from both diseases. After 40 weeks of gestation, a normal male infant was delivered.

Adult↗
PubMed1993

A new syndrome?

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Abnormalities, Multiple↗
PubMed1992

A mathematical model for the computation of the forces exerted by the facial orthopedic mask.

This study presents a model for the computation of the forces exerted on the chin and on the forehead by the facial orthopedic mask in skeletal Class III malocclusions. Cephalometric data as well as geometry of the mask are taken into account to simulate in quantitative terms the entire approach. A computer program has been implemented to validate the model on a group of patients. Despite the approximations about the mechanical characteristics of the appliance and of the constraints (rigid body, ideal constraints) and despite the unavoidable errors in the estimation of the geometric parameters (dimensions and angles), it is shown that the computation of the forces (in orientation and in magnitude) at the forehead and at the chin is possible. Some practical applications of the model are presented.

Adolescent↗