Biomedical subjects

Corrado Angelini

Publications and source records attributed to Corrado Angelini.

30 records · Page 2Linked to original sources

PubMed2004

Motor function-muscle strength relationship in spinal muscular atrophy.

The relationship between motor function and muscle strength in patients with spinal muscular atrophy (SMA) is still controversial. In 120 genetically proven SMA patients, aged 5 years or older, we measured muscle strength in the arms and legs by a hand-held dynamometer, forced vital capacity by a spirometer, and the time needed to walk 10 m, arise from the floor, and climb steps. SMA patients had markedly reduced muscle strength, approximating 20% of that predicted from age- and gender-matched normative data. Knee extensors were the weakest muscles in SMA patients. The young ambulant SMA patients performed better than adults in all the timed tests and had greater muscle strength on knee extension. This study shows a good relationship between motor ability and muscle strength in SMA and confirms that age-related loss of function in SMA is due to loss of muscle strength.

Adolescent↗

PubMed2004

The role of botulinum toxin injection and upper esophageal sphincter myotomy in treating oropharyngeal dysphagia.

The aims of this study were to assess the efficacy and safety of botulinum toxin (BoTox) injection in the cricopharyngeus muscle (CP) and CP myotomy in patients with oropharyngeal dysphagia (OPD) and to identify factors predicting the outcome of these treatments. The study involved patients with persistent OPD despite 2-6 months of rehabilitation, who all underwent clinical evaluation, esophageal manometry, upper gastrointestinal endoscopy, and videofluoroscopy (VFS). Patients received 5-10 BoTox units injections in the CP, identified by electromyography. Surgical myotomy of the upper esophageal sphincter was performed when dysphagia persisted after two BoTox injections. After treatment, patients were reevaluated with clinical interviews and VFS. The study population included 21 patients (15 mean and 6 women; median age, 68 years), classified into three groups, based on the etiology of their OPD: eight (38%) had central nervous system abnormalities, five (24%) had peripheral nerve disease, and eight (38%) were classified as idiopathic. The median time since the onset of dysphagia was 18 months. Thirteen of 21 patients (62%) needed supplemental/total gastrostomy feeding, and 5 of 21 (24%) had tracheostomy. One patient died, on posttreatment day 7, due to massive aspiration. No other BoTox-related complications were observed. After BoTox injection, dysphagia improved in 9 of 21 (43%) patients. Severely altered VFS findings and CP incoordination or low activity predicted BoTox failure at multivariate analysis. Dysphagia improved in 8 of 11 (72.7%) patients who failed to respond to BoTox and underwent myotomy. A mild impairment of VFS findings and a higher pressure of pharyngeal contractions best predicted response to BoTox with or without myotomy. BoTox injection can be used as the first therapeutic option in patients with OPD: it is safe and simple and relieves dysphagia in 43% of cases. If BoTox fails, CP myotomy can be offered to patients with preserved oral and tongue activity at VFS and an intact bolus propulsion ability on manometry.

Aged↗

PubMed2003

Phenotype modulators in myophosphorylase deficiency.

Myophosphorylase deficiency is characterized by exercise intolerance, muscle cramps, and recurrent myoglobinuria. Some patients are severely affected, whereas others are minimally affected or asymptomatic. The molecular basis of the disease has been elucidated but does not provide an explanation for the clinical variability. In a large cohort of patients with myophosphorylase deficiency, we tested the hypothesis that polymorphic variants in either myoadenylate deaminase (MADA) or angiotensin-converting enzyme (ACE) could act as modulators of phenotype expression. Forty-seven patients were evaluated. Clinical severity was assessed according to a severity scale of four grades. MADA activity was studied by histochemical and biochemical analysis of muscle, and the Q12X mutation in the adenine monophosphate deaminase 1 gene (AMPD1) and the insertion/deletion polymorphism in the ACE gene were assessed genetically. A complete MADA defect together with the Q12X mutation was detected in one severely affected patient. Eleven patients were heterozygous for the Q12X mutation. There was no association between clinical grading and MADA status. In contrast, we found a highly significant (p < 0.01) association between ACE genotype and clinical severity, with strong correlation between severe phenotype and number of D alleles. We show that ACE insertion/deletion polymorphism may play a significant role as phenotype modulator in McArdle's disease.

AMP Deaminase↗

PubMed2003

Clinical and molecular study in congenital muscular dystrophy with partial laminin alpha 2 (LAMA2) deficiency.

Complete laminin alpha2 (LAMA2) deficiency causes approximately half of congenital muscular dystrophy (CMD) cases. Many loss-of-function mutations have been reported in these severe, neonatal-onset patients, but only single missense mutations have been found in milder CMD with partial laminin alpha2 deficiency. Here, we studied nine patients diagnosed with CMD who showed abnormal white-matter signal at brain MRI and partial deficiency of laminin alpha2 on immunofluorescence of muscle biopsy. We screened the entire 9.5 kb laminin alpha2 mRNA from patient muscle biopsy by direct capillary automated sequencing, single strand conformational polymorphism (SSCP), or denaturing high performance liquid chromatography (DHPLC) of overlapping RT-PCR products followed by direct sequencing of heteroduplexes. We identified laminin alpha2 sequence changes in six of nine CMD patients. Each of the gene changes identified, except one, was novel, including three missense changes and two splice-site mutations. The finding of partial laminin alpha2 deficiency by immunostaining is not specific for laminin alpha2 gene mutation carriers, with only two patients (22%) showing clear causative mutations, and an additional three patients (33%) showing possible mutations. The clinical presentation and disease progression was homogeneous in the laminin alpha2-mutation positive and negative CMD patients.

Clubfoot↗

PubMed2003

Loss of calpain-3 autocatalytic activity in LGMD2A patients with normal protein expression.

The diagnosis of limb girdle muscular dystrophy (LGMD) type 2A (due to mutations in the gene encoding for calpain-3) is currently based on protein analysis, but mutant patients with normal protein expression have also been identified. In this study we investigated 150 LGMD patients with normal calpain-3 protein expression, identified gene mutations by an allele-specific polymerase chain reaction test, and analyzed the mutant calpain-3 catalytic activity. Four different mutations were found in eight patients (5.5%): a frame-shifting deletion (550 A del) and three missense (R490Q, R489Q, R490W). Patients with normal calpain-3 protein expression on Western blot are a considerable proportion (20%) of our total LGMD2A population. While in control muscle the calpain-3 Ca(++)-dependent autocatalytic activity was evident within 5 minutes and was prevented by ethylene diaminetetraacetic acid, in all mutant patient samples the protein was not degraded, indicating that the normal autocatalytic function had been lost. By this new functional test, we show that conventional protein diagnosis fails to detect some mutant proteins, and prove the pathogenetic role of R490Q, R489Q, R490W missense mutations. We suggest that these mutations impair protein activity by affecting interdomain protein interaction, or reduce autocatalytic activity by lowering the Ca(++) sensitivity.

Adolescent↗

PubMed2003

Novel spastin mutations and their expression analysis in two Italian families.

Mutations in spastin cause the most common form of pure autosomal dominant hereditary spastic paraparesis (SPG4). Here, we report two Italian families affected with SPG4-linked HSP harboring two novel spastin mutations. SSCP/sequencing analysis of the spastin gene showed a single base pair deletion causing a frame-shift in one family (1442delT) and a missense mutation (1726T>C) resulting in a leucine to proline amino-acid change (L534P) in the other family. Total RNA from the mutant and the wild-type spastin allele in muscle biopsies from patients from the two affected families was quantitated. RNA expression was almost absent from the spastin allele harboring the single base pair deletion, while it was nearly normal for the spastin allele harboring the missense mutation. These data suggest that varying spastin RNA levels are found in out-of-frame and missense spastin mutations and imply different mechanisms involved in the molecular pathology of SPG4 linked HSP.

Adenosine Triphosphatases↗

PubMed2003

Role of gabapentin in spinal muscular atrophy: results of a multicenter, randomized Italian study.

Recent studies suggest that gabapentin has a neuroprotective effect in experimental models of motoneuron disease. We carried out a multicenter, randomized, controlled trial of gabapentin versus no treatment in 120 patients with type II or III spinal muscular atrophy for 12 months. We assessed maximum voluntary isometric contraction with a handheld myometer and calculated an arm megascore (summing elbow flexion, hand grip, and three-point pinch scores), and a leg megascore (summing knee flexion, knee extension, and foot extension scores). Forced vital capacity and timed tasks were also evaluated. Arm megascore improved by at least 30% in 24.6% of treated and 16.9% of untreated patients (relative risk = 1.45; 95% confidence interval = 0.71-2.97). The leg megascore improved by at least 30% in 37.7% of treated and 20.3% of untreated patients (relative risk = 1.85; 95% confidence interval = 1.02-3.37). We conclude that gabapentin produced a significant improvement in leg megascore at 6 months, which was more evident at 12 months, with a trend for improvement in arm megascore at 12 months. The treatment had no effect on forced vital capacity or timed functional tests.

Acetates↗

PubMed2003

Decreased fatty acid beta-oxidation in riboflavin-responsive, multiple acylcoenzyme A dehydrogenase-deficient patients is associated with an increase in uncoupling protein-3.

Riboflavin-responsive, multiple acylcoenzyme A dehydrogenase deficiency (RR-MAD), a lipid storage myopathy, is characterized by, among others, a decrease in fatty acid (FA) beta-oxidation capacity. Muscle uncoupling protein 3 (UCP3) is up-regulated under conditions that either increase the levels of circulating free FA and/or decrease FA beta-oxidation. Using a relatively large cohort of seven RR-MAD patients, we aimed to better characterize the metabolic disturbances of this disease and to explore the possibility that it might increase UCP3 expression. A battery of biochemical and molecular tests were performed, which demonstrated decreases in FA beta-oxidation and in the activities of respiratory chain complexes I and II. These metabolic alterations were associated with increases of 3.1- and 1.7-fold in UCP3 mRNA and protein expression, respectively. All parameters were restored to control values after riboflavin treatment. We postulate that the up-regulation of UCP3 in RR-MAD is due to the accumulation of muscle FA/acylCoA. RR-MAD is an optimal model to support the hypothesis that UCP3 is involved in the outward translocation of an excess of FA from the mitochondria and to show that, in humans, the effects of FA on UCP3 expression are direct and independent of fatty acid beta-oxidation.

Acyl-CoA Dehydrogenase↗

PubMed2002

Gene expression profiling in dysferlinopathies using a dedicated muscle microarray.

We have performed expression profiling to define the molecular changes in dysferlinopathy using a novel dedicated microarray platform made with 3'-end skeletal muscle cDNAs. Eight dysferlinopathy patients, defined by western blot, immunohistochemistry and mutation analysis, were investigated with this technology. In a first experiment RNAs from different limb-girdle muscular dystrophy type 2B patients were pooled and compared with normal muscle RNA to characterize the general transcription pattern of this muscular disorder. Then the expression profiles of patients with different clinical traits were independently obtained and hierarchical clustering was applied to discover patient-specific gene variations. MHC class I genes and genes involved in protein biosynthesis were up-regulated in relation to muscle histopathological features. Conversely, the expression of genes codifying the sarcomeric proteins titin, nebulin and telethonin was down-regulated. Neither calpain-3 nor caveolin, a sarcolemmal protein interacting with dysferlin, was consistently reduced. There was a major up-regulation of proteins interacting with calcium, namely S100 calcium-binding proteins and sarcolipin, a sarcoplasmic calcium regulator.

Adolescent↗

PubMed2002

Detection of HTLV-I tax-rex and pol gene sequences of thymus gland in a large group of patients with myasthenia gravis.

We report in this study the use of polymerase chain reaction (PCR) for the amplification of the genomic DNA, isolated from thymic tissue, using the primers flanking HTLV-I/II tax-rex genes and the sequence method to analyze the HTLV-I pol sequence of 27 Italian patients with myasthenia gravis. These molecular methods showed that 92.5% of patients tested positive for tax gene and 55% for pol genes; 55.5% samples were positive for both the tax gene of HTLV-I/II, and the pol gene of HTLV-I. Histologic investigation of the thymus showed that 15 samples had thymic hyperplasia, 93% tested positive for the tax gene, and 40% tested positive for both the tax and pol genes of HTLV-I. In contrast, 91.6% of thymoma-positive samples were positive for tax gene I/II and 75% positive for both genes, tax and pol type I. The sequence analysis of PCR product for tax and pol genes confirmed that these amplified products were HTLV-I, with minimal variations. Our date suggested that either HTLV-I or part of the virus genome is involved in the etiopathogenesis of myasthenia gravis.

Adult↗

PubMed2002

Integrin alpha 7 beta 1 in muscular dystrophy/myopathy of unknown etiology.

To investigate the role of integrin alpha 7 in muscle pathology, we used a "candidate gene" approach in a large cohort of muscular dystrophy/myopathy patients. Antibodies against the intracellular domain of the integrin alpha 7A and alpha 7B were used to stain muscle biopsies from 210 patients with muscular dystrophy/myopathy of unknown etiology. Levels of alpha 7A and alpha 7B integrin were found to be decreased in 35 of 210 patients (approximately 17%). In six of these patients no integrin alpha 7B was detected. Screening for alpha 7B mutation in 30 of 35 patients detected only one integrin alpha 7 missense mutation (the mutation on the second allele was not found) in a patient presenting with a congenital muscular dystrophy-like phenotype. No integrin alpha 7 gene mutations were identified in all of the other patients showing integrin alpha 7 deficiency. In the process of mutation analysis, we identified a novel integrin alpha 7 isoform presenting 72-bp deletion. This isoform results from a partial deletion of exon 21 due to the use of a cryptic splice site generated by a G to A missense mutation at nucleotide position 2644 in integrin alpha 7 cDNA. This spliced isoform is present in about 12% of the chromosomes studied. We conclude that secondary integrin alpha 7 deficiency is rather common in muscular dystrophy/myopathy of unknown etiology, emphasizing the multiple mechanisms that may modulate integrin function and stability.

Alternative Splicing↗

PubMed2002

Investigating the mechanism of chromosomal deletion: characterization of 39 deletion breakpoints in introns 47 and 48 of the human dystrophin gene.

The region of the dystrophin gene containing introns 45-50 is characterized by a high rate of recombination events that give rise to large deletions causing dystrophinopathy. The nucleotide sequence of this intronic region has recently been released in GenBank. With the aim of further understanding the mechanism favoring the occurrence of these deletions, we have characterized the distribution of introns 47 and 48 deletion endpoints in 39 dystrophinopathy patients. In 14 of these patients we were able to sequence the break junction. On these sequences we were able to identify several intronic motifs that could predispose to DNA double-strand breaks. Our results, combined with other literature data, show that unequal homologous recombination is a very poorly represented event in the dystrophin gene, whereas junction features are suggestive of a model of recombination in which DNA double-strand breaks are incorrectly repaired by a nonhomologous end-joining mechanism. The correlation among recombination rate, deletion frequency, and percentage of repetitive elements is discussed.

Amino Acid Sequence↗