1/5. Novel mutations of TGM1 in a child with congenital ichthyosiform erythroderma.We report novel mutations in the transglutaminase (TGase) 1 gene (TGM1) in a Japanese boy with non-bullous congenital ichthyosiform erythroderma (NBCIE). The patient showed fine, grey or light-brown scales on an erythematous skin. An in situ TGase activity assay detected markedly reduced TGase activity in the patient's epidermis. Electron microscopy revealed incomplete thickening of the cornified cell envelope during keratinization in the epidermis. Sequencing of the entire exons and exon-intron borders of TGM1 revealed that the proband was a compound heterozygote for two novel mutations, 9008delA and R388H. In lamellar ichthyosis, most previously reported TGM1 mutations have been located in the central core domain or upstream of the TGase 1 molecule. In the present NBCIE patient, the frameshift mutation 9008delA resulting in a premature termination codon at the tail of the TGase 1 peptide was in the beta-barrel 2 domain (C-terminal end domain) of the peptide, far from the active sites of the TGase 1 molecule, and the mis-sense mutation R388H was in the core domain.- - - - - - - - - - ranking = 1keywords = epidermis (Clic here for more details about this article) |
2/5. Identification of two novel nonsense mutations in the transglutaminase 1 gene in a Hungarian patient with congenital ichthyosiform erythroderma.Congenital ichthyosiform erythroderma (CIE) belongs together with lamellar ichthyosis (LI) to the group of autosomal recessive congenital ichthyoses (ARCI). Mutations in the transglutaminase (TGase) 1 gene (TGM1) have been identified in several families with LI and in some families with CIE. We report a case of CIE with two new nonsense mutations: a C7780G transversion in exon 11 resulting in a premature stop codon at aminoacid residue Y503X and a C8533G transversion in exon 13 leading to a nonsense mutation at S669X. These mutations were also identified in a heterozygous pattern in the unaffected parents. These two termination-codons result in the translation of a truncated protein at the C-terminal end domain of the TGM 1 molecule. B.C1 monoclonal antibody failed to detect TGase 1 in the patient's skin sample, and TGase activity measured by monodansyl cadaverine-incorporation showed the reduced TGase activity at the distribution of TGase 1 in the epidermis.- - - - - - - - - - ranking = 0.5keywords = epidermis (Clic here for more details about this article) |
3/5. epidermal growth factor receptors in genetically induced hyperproliferative skin disorders.The presence and morphologic distribution of epidermal growth factor receptor (EGF-R) were investigated in a variety of genetic disorders that affect human epidermis. These diseases included various forms of ichthyoses as well as restrictive dermopathy and the child syndrome (congenital hemidysplasia-ichthyosiform erythroderma-limb defects). The distribution of EGF-R was detected by immunohistochemical techniques. Increased staining of immunoreactive EGF-R was frequently, but not always, seen in lesions with experimental or clinical evidence of hyperproliferation, suggesting an increased potential to respond to endogenous levels of either transforming growth factor-alpha or EGF. The finding that EGF-R levels are not always increased in congenital epidermal disorders indicated that the presence of this receptor pathway is not simply a marker for aberrant epidermis.- - - - - - - - - - ranking = 1keywords = epidermis (Clic here for more details about this article) |
4/5. child syndrome: analysis of abnormal keratinization and ultrastructure.A new patient with child syndrome (congenital hemidysplasia, ichthyosiform erythroderma, and limb defects), the thirtieth in the literature, was observed for over three years. Initially, the right-sided lesion spared the breast area. At 10 months of age the trunk lesion extended to cover the entire area of the right chest. At age 20 months the patient developed linear, bandlike, keratotic, brown-black lesions on her left thigh that subsided within six weeks, leaving a slight hyperpigmentation. This patient was studied by routine histologic methods as well as with markers of keratinization and electron microscopy. In hematoxylin and eosinstained sections, parakeratosis and orthokeratosis alternated. In some parakeratotic areas, large granular cells, and in others, ghost granular cells, were present. The latter showed basophilic cytoplasm, and palestaining or vacuolated nucleus and were seen either above the normal granular layer or without it. Although regional variations existed, basal cell-type keratins as recognized by AE1 continued to be expressed in suprabasal layers. Filaggrin- and involucrin-positive layers were expanded, particularly the latter, down to the lower prickle cell layer. Ultrastructurally, numerous lamellar or membranous structures were found in upper layers of the epidermis, both intracellulary and intercellularly. Normal cementsomes coexisted with these abnormal lamellar structures, and it was thought that the latter represent modified cementsomes because the discharge of those from the cell periphery was often detected.- - - - - - - - - - ranking = 0.5keywords = epidermis (Clic here for more details about this article) |
5/5. 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.- - - - - - - - - - ranking = 0.5keywords = epidermis (Clic here for more details about this article) |