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M L Carpentieri

Publications and source records attributed to M L Carpentieri.

5 recordsLinked to original sources

Autonomic dysfunction in children with Hirschsprung's disease.

During embryogenesis, two different transmembrane receptors, Ret and Ednrb, together with their ligands, respective, GDNF and endothelin-3, are involved in the migration and differentiation of enteric ganglion cells, sympathetic neurons and melanocytes from the neural crest. Mutations in these genes have been found in a number of human and murine neurocristopathies, including Hirschsprung's disease. RET and GDNF knockouts suggest that they are involved in a correct autonomic nervous system formation. The aim of this study is the evaluation of the autonomic nervous system in patients with Hirschsprung's disease. Seventeen children (mean age: 8.6 years) with Hirschsprung's disease and 19 age- and sex-matched control children (mean age: 9.9 years) underwent pupillary and cardiovascular testing of sympathetic adrenergic and cholinergic function and cardiovagal cholinergic function. Seven of 17 patients with Hirschsprung's disease were affected by autonomic dysfunction. Three of seven patients had evidence of sympathetic denervation, two showed a parasympathetic dysfunction, whereas the remaining two had dysfunction of both sympathetic and parasympathetic tests. Our data in a small number of patients with Hirschsprung's disease show that a subset of these patients exhibits measurable autonomic dysfunction. A RET mutation has been found in one of them. As for the absence of the enteric ganglion cells, autonomic dysfunction in these subjects seems to be polygenic.

Adolescent↗

Cell-specific transcriptional regulation and reactivation of galectin-1 gene expression are controlled by DNA methylation of the promoter region.

The galectin-1 gene is developmentally regulated gene whose activity is strongly modulated during cell differentiation and transformation. We have previously shown that galectin-1 promoter constructs are highly active when transiently transfected in cells both expressing and not expressing the endogenous gene and that the basal activity is determined by a small region encompassing the transcription start site (from positions -50 to +50). We have now investigated the role of DNA methylation in galectin-1 gene expression. Southern blot analysis with HpaII and MspI endonucleases and sodium bisulfite analysis of genomic DNA from expressing and nonexpressing cell lines and cell hybrids showed a close correlation between gene activity and demethylation of the 5' region of the galectin-1 gene. We found that the galectin-1 promoter region is fully methylated, at every CpG site on both strands, in nonexpressing differentiated rat liver (FAO) and thyroid (PC C13) cells and unmethylated in the expressing undifferentiated liver (BRL3A) and thyroid transformed (PC myc/raf) cell lines. In addition, reactivation of the silent FAO alleles in FAO-human osteosarcoma (143tk-) hybrid cells is accompanied by a complete demethylation of the promoter region. Finally, when galectin-1 chloramphenicol acetyltransferase (CAT) promoter constructs were methylated in vitro by SssI methylase at every cytosine residue of the CpG doublets and transfected into mouse fibroblasts, the transcription of the CAT reporter gene was strongly inhibited.

Animals↗

Cranioectodermal dysplasia: a new patient with an inapparent, subtle phenotype.

Cranioectodermal dysplasia is a rare syndrome characterized by craniofacial and skeletal anomalies and ectodermal dysplasia. Life-threatening associated conditions (i.e., kidney failure and abnormal regulation of the parathyroid-bone axis) can also develop. We report a patient whose features are suggestive of an inapparent, subtle phenotype of the syndrome. The patient is a 4-year-old girl with only dolichocephaly and clinodactyly; microdontia, hypodontia, and taurodontia (i.e., cone-shaped teeth); anteverted nares, full cheeks, and everted lower lip; epicanthal folds, hypertelorism and hyperopia; and corpus callosum hypoplasia. She has no rhizomelic limb shortening or hair abnormalities. In view of the rarity of the cranioectodermal dysplasias, the variability of the phenotype, and the uncertain outcome of some previously described patients, we believe this inapparent, subtle case should reported to enable better understanding and treatment of this rare syndrome.

Bone and Bones↗