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G Rotondo

Publications and source records attributed to G Rotondo.

At least 55 records · Page 3Linked to original sources

[Equitable indemnity].

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Disability Evaluation↗

[Expression of a defect in the respiratory chain in cultured human cells].

Large scale deletions of mitochondrial DNA (mtDNA) or altered inter-genomic regulation in skeletal muscle have been demonstrated in patients with mitochondrial encephalomyopathies due to Cytochrome C oxidase (COx) deficiency. We have analyzed by Southern blotting and Polymerase Chain Reaction (PCR) the mtDNA in primary muscle cultures (myoblast-myotube stages and at clonal densities) and in fibrogenic subclones obtained from 9 patients with partial COx deficiency who had in their muscle biopsy a subpopulation of mtDNA showing deletions of variable size (between 2.1 and 6.5 Kb). Only in the cultures from one patient, southern analysis revealed in myoblasts and myotubes a mtDNA almost identical to that found in the original muscle biopsy and persistence of deletion in muscle cells grown at clonal densities. The deletion was detectable in fibrogenic lineage only by PCR amplification. The deleted mtDNA molecules were detectable in myogenic or fibrogenic cultures from other patients only by PCR amplification. The different amounts of deleted mtDNA in the various tissues could be due either to an unequal distribution of the altered mtDNA during embryogenesis with amplification of deleted molecules in myogenic lineage or could result from negative selection against the altered mtDNA in rapidly proliferating cells, such as fibroblasts.

Blotting, Southern↗

Muscleblind-like protein 1 nuclear sequestration is a molecular pathology marker of DM1 and DM2.

Myotonic dystrophies (DM) are repeat expansion diseases in which expanded CTG (DM1) and CCTG (DM2) repeats cause the disease. Mutant transcripts containing CUG/CCUG repeats are retained in muscle nuclei producing ribonuclear inclusions, which can bind specific RNA-binding proteins, leading to a reduction in their activity. The sequestration of muscleblind-like proteins (MBNLs), a family of alternative splicing factors, appears to be involved in splicing defects characteristic of DM pathologies. To determine whether MBNL1 nuclear sequestration is a feature of DM pathologies, we have examined the in vivo distribution of MBNL1 in muscle sections from genetically confirmed DM1 (n=7) and DM2 (n=9) patients, patients with other myotonic disorders (n=11) and from patients with disorders caused by repeat expansions, but not DM1/DM2 (n=3). The results of our immunofluorescence study indicate that, among patients examined, MBNL1 nuclear sequestration in protein foci is a molecular pathology marker of DM1 and DM2 patients where ribonuclear inclusions of transcripts with expanded CUG/CCUG repeats are also present. These findings indicate that MBNLs might be important targets for therapeutic interventions to correct some of the specific features of DM pathology.

Cell Nucleus↗