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S Servidei

Publications and source records attributed to S Servidei.

At least 91 records · Page 5Linked to original sources
PubMed1993

Cardiomyopathy may be the only clinical manifestation in female carriers of Duchenne muscular dystrophy.

Cardiomyopathy was reported in a few Duchenne muscular dystrophy (DMD) carriers with clinical evidence of myopathy. We report two carriers with dilated cardiomyopathy, increased serum CK, and no symptoms of muscle weakness. In heart biopsies of both patients, dystrophin-the protein product of DMD locus--was absent in many fibers. Dilated cardiomyopathy may be the only manifestation of dystrophin gene mutation in carriers.

Adult↗
PubMed1993

Clinical features associated with the A-->G transition at nucleotide 8344 of mtDNA ("MERRF mutation").

We looked for the A-->G transition at position 8344 of mtDNA in 150 patients, most of them with diagnosed or suspected mitochondrial disease, to assess the specificity of this mutation for the MERRF phenotype, to define the clinical spectrum associated with the mutation, and to study the relationship between percentage of mutation in muscle and clinical severity. Our results confirm the high correlation between the A-->G transition at position 8344 and the MERRF syndrome, but they also show that this mutation can be associated with other phenotypes, including Leigh's syndrome, myoclonus or myopathy with truncal lipomas, and proximal myopathy. The absence of the mutation in four typical MERRF patients suggests that other mutations in the tRNA(Lys) gene, or elsewhere in the mitochondrial DNA, can produce the same phenotype.

Adult↗
PubMed1992

Giant axonal neuropathy: report on a case with focal fiber loss.

We report on a 5 1/2 year-old boy with chronic progressive polyneuropathy, ataxia, and pyramidal signs. His hair was not curled. Sural nerve biopsy disclosed many axons enlarged by accumulation of 10-nm neurofilaments and a marked variability in the number of myelinated fibers as well as in the amount of axonal enlargements among different fascicles. These findings and the electrophysiological data were consistent with a giant axonal polyneuropathy with a multifocal fiber loss.

Axons↗
PubMed1992

Somatosensory and motor evoked potentials in the assessment of cerebrotendinous xanthomatosis before and after treatment with chenodeoxycholic acid: a preliminary study.

We studied two unrelated patients with cerebrotendinous xanthomatosis, in whom clinical examination revealed central nervous system long tract involvement. Brain and spinal cord magnetic resonance imaging showed no signs supporting the involvement of the long pathways. Somatosensory and motor evoked potentials demonstrated central sensory and motor conduction abnormalities, which suggested distal degeneration of longer fibers, rather than scattered focal lesions in the CNS. In one of the patients the neurophysiological study was repeated 6 and 12 months after the beginning of treatment with chenodeoxycholic acid, showing a progressive improvement. Therefore, our data suggest that central motor and sensory conduction studies may be useful in the assessment of the disease and in monitoring treatment.

Adult↗
PubMed1992

Fatal infantile liver failure associated with mitochondrial DNA depletion.

A 3-month-old girl was admitted to the hospital because of hypotonia and frequent vomiting. She had severe metabolic acidosis and her liver function was abnormal. Hepatomegaly and rapidly progressive liver failure developed, and she died at 4 months of age. Two half-siblings from a different mother had died in infancy of an undiagnosed myopathy. The liver was fatty and hepatocytes were filled with large and small lipid droplets. Other tissues were morphologically normal. The respiratory chain enzymes containing subunits encoded by mitochondrial DNA were markedly decreased in liver, partially decreased in muscle, but normal in other tissues. Southern blot analysis showed 90% depletion of mitochondrial DNA in liver, 53% depletion in muscle, and normal amounts in other tissues. This is the second case of fatal infantile liver failure associated with mitochondrial DNA depletion. This pathogenetic mechanism should be considered in infants with multiple respiratory chain defects and variable tissue expression.

Acidosis, Lactic↗
PubMed1992

Benign monomelic amyotrophy of lower limb: report of three cases.

Three patients with wasting confined to a single lower limb are reported. The characteristic features were: sporadic occurrence, insidious onset with slow progression and in 2 cases arrested course for at least 4 years, wasting out of proportion with disability, absence of sensory, pyramidal tract or bulbar signs. CK, motor and sensory conductions, and lumbar MRI were normal. Muscle CT showed selective loss of muscle tissue and fat replacement in posterior leg muscles. Quantitative electromyography and histologic findings revealed neurogenic features not only in the affected legs, but also in clinically uninvolved limbs. Monomelic amyotrophy of lower limb is a variant of spinal muscular atrophy with a benign course. However, as in the early stages of the disease there are no distinctive clinical or laboratory findings with other motor neuron diseases, the diagnosis of monomelic amyotrophy may be made only retrospectively after a prolonged observation.

Adult↗
PubMed1992

Disorders associated with depletion of mitochondrial DNA.

Quantitative defects of mtDNA have been recently described in patients with fatal mitochondrial disease of early infancy or mitochondrial myopathy of childhood. There was variable tissue expression and depletion of up to 98% of mtDNA in affected tissues. Pedigree analysis was compatible with mendelian inheritance, suggesting faulty communication between nuclear and mitochondrial genomes, but the primary molecular lesion is unknown. In muscle, morphological studies allowed to correlate mtDNA depletion, absence of mtDNA-encoded peptides, mitochondrial proliferation, and loss of cytochrome c oxidase (COX) activity in individual fibers.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Polyglucosan body disease.

Adult polyglucosan disease has been described in 15 cases. All had signs of peripheral neuropathy, upper motor neuron signs, and 12 of the 15 had sphincter problems. Dementia was prominent in 8 of 15 cases. We reported 2 cases that contained these clinical features. Electrophysiological studies showed axonal neuropathy. Somatosensory evoked potentials on the second patient were abnormal. Sural nerve biopsy showed clusters of polyglucosan bodies. Although the presence of polyglucosan bodies in biopsy is nonspecific, the number as well as the clinical features are necessary to make the diagnosis. Branching enzyme activity in muscle extracts of the muscles were normal. Hence, a specific enzyme abnormality is not yet known.

Fecal Incontinence↗
PubMed1991

Neuromyopathy and restrictive cardiomyopathy with accumulation of intermediate filaments: a clinical, morphological and biochemical study.

The clinical, morphological and biochemical findings of a sporadic case, showing accumulation of desmin-type intermediate filaments in skeletal muscle and myocardium are described. Desmin storage was demonstrated by immunofluorescence, sodium dodecyl sulfate gel electrophoresis and two-dimensional gel electrophoresis. These findings are in agreement with those of Rappaport et al. (FEBS lett. 231:421-425, 1989). A sensory-motor polyneuropathy was established by electrophysiological studies and, ultrastructurally, intramuscular nerves showed accumulation of neurofilaments and neurotubules with formation of axonal spheroids. These findings are discussed considering all previous reports with related conditions.

Cardiomyopathy, Dilated↗
PubMed1991

Late onset lipid storage myopathy due to multiple acyl CoA dehydrogenase deficiency triggered by valproate.

Late onset Multiple Acyl CoA dehydrogenase (MAD) deficiency myopathy is a rare disorder. Only five cases have been reported. We report one case with MAD deficiency in which the clinical features appeared during valproic acid therapy. A 47-yr-old man taking valproic acid for 4 months presented nocturnal calf cramps, exercise intolerance, difficulty in climbing stairs and shortness of breath. Muscle biopsy revealed ragged red fibres and neutral lipid storage. Electron microscopy showed enlarged abnormal mitochondria with abnormal internal structure. The total and free muscle carnitine was decreased. The activities of all short, medium and long chain acyl CoA dehydrogenases were 40% of the normal. In this case a partial defect of MAD is noted, possibly triggered by valproic acid, causing the clinical manifestations of the pre-existing myopathy. After discontinuation of the drug a clinical improvement was observed while therapy with riboflavin resulted in a total relief of the symptoms.

Acyl-CoA Dehydrogenase↗
PubMed1991

Differential diagnosis of fatal and benign cytochrome c oxidase-deficient myopathies of infancy: an immunohistochemical approach.

To differentiate the 2 major myopathies of infancy due to cytochrome c oxidase (COX) deficiency, we studied muscle biopsies from 4 patients with fatal myopathy and 4 with benign myopathy using biochemical, histochemical, and immunohistochemical techniques. Immunohistochemistry with antibodies directed against individual subunits of COX differentiated the 2 phenotypes: the fatal infantile myopathy was characterized by absence of the nuclear DNA (nDNA)-encoded subunit VIIa,b of COX, while in the benign myopathy both VIIa,b and the mitochondrial DNA (mtDNA)-encoded subunit II were absent. Early differential diagnosis between fatal and benign COX-deficient myopathies is of critical importance for prognosis and management of these infants, because the benign form is initially life-threatening but ultimately reversible.

Biopsy↗
PubMed1991

Dominantly inherited mitochondrial myopathy with multiple deletions of mitochondrial DNA: clinical, morphologic, and biochemical studies.

We studied a large family with a dominantly inherited mitochondrial myopathy characterized by progressive external ophthalmoplegia, dysphagia, cataract, lactic acidosis, exercise intolerance, and early death. Morphologic studies of muscle biopsies suggested mitochondrial heteroplasmy and revealed ragged-red fibers and decreased histochemical reactions for cytochrome c oxidase and succinate dehydrogenase. Biochemistry showed a partial defect of cytochrome c oxidase and a mild generalized reduction of other mitochondrial enzymes requiring mitochondrial DNA-encoded subunits. Southern blot analysis and PCR amplification showed mitochondrial DNA deletions in muscle of all affected members, but not in lymphocytes or fibroblasts, suggesting a tissue-specific distribution. Deletions were multiple and seemed to increase with time and to correlate with the severity of the disease.

Adult↗
PubMed1990

X-linked spinal muscular atrophy (Kennedy's syndrome). A kindred with hypobetalipoproteinemia.

Kennedy's syndrome, X-linked adult-onset bulbospinal muscular atrophy, has been described in over 30 families. The characteristic distribution of weakness creates a recognizable syndrome, augmented by frequent findings of testicular atrophy and gynecomastia. Type IV or type II hyperlipoproteinemia has been found in some families. We have studied another family with Kennedy's syndrome, this one with hypobetalipoproteinemia. The diversity of serum patterns suggests that lipoprotein abnormalities are not causally related to either the endocrinopathy or the spinal muscular atrophy. However, gene linkage studies indicate proximity of the gene for Kennedy's syndrome and the gene encoding the androgen receptor, which could explain the combination of a motor neuron disorder and the endocrine abnormalities.

Adult↗
PubMed1990

Metabolic causes of myoglobinuria.

To evaluate the proportion of cases of myoglobinuria that can be ascribed to specific metabolic defects, we have studied eight enzymes--phosphorylase, phosphorylase kinase, phosphofructokinase (PFK), phosphoglycerate kinase (PGK), phosphoglycerate mutase (PGAM), lactate dehydrogenase (LDH), carnitine palmitoyltransferase (CPT), and myoadenylate deaminase (MAD)--in muscle biopsy specimens from 77 consecutive patients with myoglobinuria (documented in 44, suspected in 33). Enzyme defects were found in 36 patients: CPT deficiency in 17, phosphorylase deficiency in 10, phosphorylase kinase deficiency in 4, MAD deficiency in 3, PGK deficiency in 1, and a combined defect of CPT and MAD in 1. Exercise was the main precipitating factor, both in patients with and in those without detectable enzymopathies. Thirty patients had specific enzymopathies without myoglobinuria: 14 had phosphorylase deficiency, 9 had MAD deficiency, 3 had phosphorylase kinase deficiency, 3 had PFK deficiency, and 1 had PGAM deficiency. Systematic biochemical evaluation of muscle biopsy specimens revealed specific enzymopathies in about half of the patients with idiopathic myoglobinuria. The rest may have blocks of metabolic pathways not yet studied routinely, such as beta oxidation, or genetic defects of the sarcolemma, such as Becker's muscular dystrophy.

AMP Deaminase↗
PubMed1990

Tissue distribution and transmission of mitochondrial DNA deletions in mitochondrial myopathies.

By using a combination of Southern blot hybridization analysis, polymerase-chain reaction amplification, and direct nucleotide sequencing, we studied deletions of mitochondrial DNA (mtDNA) in several nonfamilial patients with progressive external ophthalmoplegia and Kearns-Sayre syndrome, and in some of their direct relatives. Results suggest that the heteroplasmic mtDNA populations are already present at a very early stage of development, and that there is no direct transmission of mtDNA heteroplasmy by maternal inheritance.

Base Sequence↗
PubMed1990

Cardiomyopathy and multicore myopathy with accumulation of intermediate filaments.

A girl affected by a restrictive cardiomyopathy with neuromuscular involvement is described. Morphological examination showed a pattern of multicore myopathy and with electron microscopy a sarcoplasmic accumulation of electron dense granular and filamentous material was demonstrated both in skeletal muscle and heart. This peculiar electron dense material corresponded to increased desmin in muscle and cardiac fibres and was demonstrated immunohistochemically.

Adolescent↗
PubMed1990

Involvement of respiratory muscles in cytoplasmic body myopathy--a pathology study.

A muscle biopsy and autopsy study of a child who died at 14 months of respiratory failure is described. A diagnosis of infantile cytoplasmic body myopathy was made due to the high percentage of cytoplasmic bodies (CBs), particularly in respiratory muscles. No pathological abnormalities were found in the central nervous system, peripheral nerves or visceral organs. Immunohistochemical studies suggested that the central core of CBs was stained for fibrillary actin, being surrounded by a positive signal for desmin. A differential diagnosis as to other conditions involving proliferation of CBs is discussed.

Autopsy↗