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A Uncini

Publications and source records attributed to A Uncini.

At least 55 records · Page 3Linked to original sources
PubMed1996

Chronic progressive steroid responsive axonal polyneuropathy: a CIDP vaariant or a primary axonal disorder?

Five patients presented with chronic,, progressive, predominantly motor polyneuropathy. CSF protein content was increased in 4 patients. Motor conduction velocities and EMG were consistent with axonal involvement. Sural nerve conductions were normal in all cases and sural nerve biopsy performed in 1 patient was normal. Serum antibodies to GM1, GD1a, GD1b, and GM2 were negative. All patients improved after steroid treatment and 3 completely recovered. Because of therapeutic implications it is important to differentiate these patients from those with chronic idiopathic axonal neuropathies. It is unclear whether this is a primary axonal, probably immune-mediated, polyneuropathy, or whether it represents one extreme of the chronic inflammatory demyelinating polyradiculoneuropathy spectrum characterized by severe axonal loss. We suggest that the term "chronic inflammatory polyneuropathy," encompassing cases from pure demyelinating to pure axonal neuropathies responsive to steroids, should be reinstated and that, like in Guillain-Barré syndrome, different subtypes should be individuated.

Adolescent↗
PubMed1996

Delayed bilateral median nerve injury due to low-tension electric current.

A 6-year-old boy inserted an opened metal clip into a domestic electric outlet using the thumb and index fingers of both hands. He suffered low tension electrical shock with mild cutaneous signs. After a few weeks, he developed bilateral numbness and weakness of both hands. Electrophysiologic studies revealed bilateral median nerve sensorimotor axonal loss. Low tension electric shock could have produced delayed bilateral median nerve damage indirectly via spasm and thermal coagulation of the vasa nervorum. The pinching position of the fingers, the "circuit" of the metal clip, and the low resistance due to the thinness and moistness of child's skin may account for: 1) the absence of an electrical cutaneous burn and 2) easy volume conduction of current along the neurovascular bundle containing the median nerve.

Child↗
PubMed1996

Homozygosity and heterozygosity for the transthyretin Leu64 mutation: clinical, biochemical and molecular findings.

Transthyretin gene point mutations cause hereditary amyloidosis with an autosomal dominant pattern of inheritance. The disease usually manifests itself in heterozygous patients, although a few homozygotes have been reported. We describe two unrelated patients carrying the Leu64 mutation, one of whom presents a homozygous genotype (Family B). Homozygosity was confirmed by sequence analysis, RG-PCR and double one-dimensional electrophoresis of the plasma protein. Although the clinical picture of the homozygous patient of Family B was more severe than that shown by the heterozygous members of Family A, the variability often displayed by FAP patients does not allow any firm conclusion about the role of homozygosity in the seriousness of the disease.

Aged↗
PubMed1996

Cutaneous electromyographic silent period findings in brachial dystonia.

In this study we investigated the physiologic mechanisms in primary brachial dystonia by analyzing the cutaneous EMG silent period during isometric contraction of the opponens pollicis muscle. Results from the affected and unaffected arms of 11 patients with dystonia were compared to 7 patients with Parkinson's disease and 16 age-matched normal individuals (controls). The silent period onset latency, degree of EMG suppression during the silent period, and EMG rebound at the end of the silent period did not differ significantly between patients with dystonia and any other group. The duration of the silent period (the S-X interval), however, was significantly prolonged in dystonia (p<0.005) and in Parkinson's disease (p<0.001) in both affected and unaffected arms compared with controls. These findings suggest that mechanisms responsible for the initiation of the cutaneously induced silent period and the subsequent suppression depth of EMG activity are not affected in brachial dystonia, but the abnormally prolonged S-X intervals may reflect dysfunctional basal ganglia timing influences over spinal circuitry common to both dystonia and Parkinson's disease.

Adult↗
PubMed1995

Androgen receptor gene (CAG)n repeat analysis in the differential diagnosis between Kennedy disease and other motoneuron disorders.

An increase in the number of (CAG)n repeats in the first coding exon of the androgen receptor (AR) gene has been strongly associated with Kennedy disease (KD) (spinal and bulbar muscular atrophy). This is an X-linked hereditary disorder characterized by motoneuron degeneration occurring in adults together with gynecomastia and hyperestrogenemia. We have performed AR gene molecular analysis in several members of a large family with KD as well as in 25 sporadic patients suffering from heterogeneous motoneuron disease (MND). An increase in the length of the (CAG)n repeats was detected, as expected, in all the affected males and in obligatory carrier females, some of which had minor signs of lower motoneuron involvement. There was only one possible exception, one young male with initial signs of the disease, who had an apparent normal length allele. An increased pathological allele was also found in 3 patients with MND. This indicates that the analysis of (CAG)n repeats of the AR gene plays a role in the differential diagnosis of this heterogeneous group of neurological diseases.

Adolescent↗
PubMed1995

Differential electrophysiological features of neuropathies associated with 17p11.2 deletion and duplication.

UNLABELLED: Hereditary neuropathy with liability to pressure palsies (HNPP) and hereditary motor-sensory neuropathy type IA (HMSN IA) are quite distinct clinical entities recently associated to deletion and duplication, respectively, of the 17p11.2 segment including the gene for peripheral myelin protein 22 (PMP-22). We studied the electrophysiological features of 48 HNPP and 62 HMSN IA motor nerves. Conduction velocities (CV) and compound muscle action potential amplitudes were significantly reduced and distal latencies prolonged in HMSN IA compared to HNPP. CV was uniformly slowed in HMSN IA nerves whereas in HNPP it was focally slowed in 80% of ulnar and 12% of peroneal nerves at usual compression sites. Conduction block was present in 6% of HNPP nerves but in none of HMSN IA. IN CONCLUSION: (1) HMSN IA with 17p11.2 duplication presents marked, diffuse, and uniform slowing; (2) HNPP with 17p11.2 deletion presents focal electrophysiological abnormalities possibly correlated with the presence of tomaculae; and (3) under- and overexpression of PMP-22 in concurrence with environmental factors might be responsible for the distinctive features of HNPP and HMSN IA.

Action Potentials↗
PubMed1995

Abnormal brain and muscle energy metabolism shown by 31P-MRS in familial hemiplegic migraine.

Familial hemiplegic migraine (FHM) is a rare autosomal dominant disorder of unknown pathogenesis characterized by migraine and transitory hemiplegic attacks. We describe a kindred fulfilling the diagnostic criteria for FHM in which: (1) brain phosphorus magnetic resonance spectroscopy (31P-MRS) showed a reduced phosphocreatine content accompanied by high [ADP], high percentage of V/Vmax of ATP biosynthesis and decreased phosphorylation potential; (2) muscle 31P-MRS showed a reduced rate of phosphocreatine recovery after exercise; (3) blood lactate was increased after effort; (4) muscle biopsy showed, in one patient, rare ragged red fibers succinate-dehydrogenase positive and cytochrome c oxidase negative; (5) genetic analysis of muscle mitochondrial DNA did not show any of the two point mutations in the tRNA(Leu(UUR)) associated with the MELAS syndrome (Mitochondrial myopathy, Encephalopathy with Lactic Acidosis and Stroke-like episodes). The defective energy metabolism of brain and muscle found in this pedigree suggests a multisystemic disorder of mitochondrial function in this FHM pedigree.

Adolescent↗
PubMed1995

Familial autoimmune myasthenia gravis: report of four families.

Four families each with two patients with autoimmune myasthenia gravis or related conditions are reported. All clinical forms of myasthenia gravis were represented and different disease types were found within the same family. Either one or two generations could be affected and no association with a single HLA haplotype was found. The frequency of familial autoimmune myasthenia gravis is very low and the genetic factors involved seem to be different from MHC genes.

Adult↗
PubMed1994

Hereditary motor and sensory neuropathy with calf hypertrophy is associated with 17p11.2 duplication.

The demyelinating type of hereditary motor and sensory neuropathy (HMSN I) is characterized by progressive weakness and atrophy of leg muscles. Six patients (age, 25-79 yr) belonging to three generations had calf hypertrophy (6 of 6), foot drop or difficulty with heel walking (4 of 6), pes cavus (3 of 6), absent or depressed tendon jerks in the lower limbs (4 of 6), and mild distal sensory loss (3 of 6). No other family member had leg atrophy. Motor conduction velocities ranged from 20 to 40 m/sec. Sural nerve biopsy showed loss of large myelinated fibers, numerous onion bulbs, and segmental demyelination and remyelination. Computed tomographic scans of leg muscles and histological and morphometric findings in gastrocnemius revealed true muscular hypertrophy. Southern blot and fluorescence in situ hybridization documented the duplication of the entire 17p11.2 segment associated with classical HMSN IA. The pathogenesis of muscle hypertrophy in our cases is unclear. Chronic leg muscle weakness and long-standing partial denervation might cause calf enlargement by a combination of compensatory "work-induced" and "stretch-induced" fiber hypertrophy. Alternatively, that all the affected family members presented calf hypertrophy might suggest the action of a genetic factor associated with the duplication at 17p11.2.

Adult↗
PubMed1994

Ophthalmoplegia, demyelinating neuropathy, leukoencephalopathy, myopathy, and gastrointestinal dysfunction with multiple deletions of mitochondrial DNA: a mitochondrial multisystem disorder in search of a name.

This article describes a 37-year-old woman with progressive external ophthalmoplegia, peripheral neuropathy, and chronic intractable diarrhea. Laboratory studies disclosed lactic acidosis, ragged red fibers lacking cytochrome c oxidase, high-normal muscular mitochondrial enzymes, demyelinating neuropathy, leukoencephalopathy and multiple mitochondrial DNA deletions. This is the fourth patient described with this clinical syndrome, which represents a separate entity among multisystemic mitochondrial disorders. The patient described here is the first with this syndrome to have multiple mitochondrial DNA deletions.

Adult↗
PubMed1994

Benign monomelic amyotrophy of lower limb: a rare entity with a characteristic muscular CT.

Six patients presented with amyotrophy confined to a single lower limb and characterized by insidious onset, slow progression and later stabilization. Wasting was out of proportion with disability and there were no sensory, pyramidal tract or bulbar signs. All cases were sporadic, and there was no history of poliomyelitis. CK, anti-ganglioside antibodies, motor and sensory conductions were normal. Quantitative EMG and muscle biopsy revealed neurogenic features also in clinically unaffected limbs. Muscular CT showed selective or predominant, asymmetrical involvement of posterior leg muscles and caput longus of biceps femoris. Monomelic amyotrophy of lower limb is a clinically localized variant of spinal muscular atrophy with a particularly benign course. Although in the early stage there are no clinical or laboratory findings which allow differential diagnosis with other motor neuron diseases, the history of an amyotrophy clinically localized for more than 3 years to a lower single limb and the characteristic muscular CT pattern suggest the diagnosis since the first observation and indicate a favorable prognosis.

Adult↗
PubMed1994

Hand dystonia secondary to cervical demyelinating lesion.

Dystonia is generally considered a disease of basal ganglia. We report two patients with definite MS who acutely developed hand dystonia and athetoid movements. In both patients: 1) dystonia was electrophysiologically demonstrated by lack of reciprocal inhibition between antagonistic forearm muscles; 2) SEP from median nerve stimulation showed delayed cervical N13 and absent frontal and parietal components; 3) the long latency response after stimulation of median nerve of the affected hand was absent or delayed; 4) MRI showed lesions in the posterolateral cervical spine but no involvement of basal ganglia and thalami. We think that, in these cases, dystonia and athetoid movements could be ascribed respectively to the involvement of descending pathways regulating reciprocal inhibition of motoneurons and to the involvement of large diameter afferents due to the demyelinating lesion at the cervical level.

Adult↗
PubMed1993

Conduction abnormalities induced by sera of patients with multifocal motor neuropathy and anti-GM1 antibodies.

Increased titers of anti-GM1 antibodies have been associated with motor neuron disease and motor neuropathy with or without conduction block. To investigate the pathogenetic role of anti-GM1 antibodies we injected into rat tibial nerves sera from patients with multifocal motor neuropathy and conduction block (MMN) or progressive spinal muscular atrophy (PMA), both presenting anti-GM1 antibodies. Sera of patients with MMN produced reduction of amplitude and dispersion of compound muscle action potential from proximal stimulation. Morphometry revealed demyelination in 6.2% of fibers. Sera of patients with PMA did not produce clear-cut electrophysiological or morphological changes. Differential effects of sera from patients presenting high-titer anti-GM1 antibodies, but with distinct clinical syndromes, might depend on differences in anti-GM1 antibody affinity, valency, or ability to fix complement. Alternatively, circulating factors other than, or in addition to, anti-GM1 antibodies present in sera of patients with MMN, but not of PMA patients, might be responsible for conduction abnormalities and reproduce them after passive transfer.

Animals↗
PubMed1993

Sensitivity of three median-to-ulnar comparative tests in diagnosis of mild carpal tunnel syndrome.

We studied 193 hands of 113 patients referred for typical carpal tunnel syndrome (CTS). Ninety-five (49%) hands had normal median distal motor latency (< or = 4.2 ms) and normal or borderline sensory conduction velocity from digit 2 stimulation (> or = 45 m/s). In these cases we performed three median to ulnar comparative tests: (1) difference between median and ulnar distal motor latencies recorded from the second lumbrical and interossei muscles (2L-INT); (2) difference between median and ulnar sensory latencies from digit 4 stimulation (D4M-D4U); and (3) difference between median and ulnar mixed nerve latencies from palmar stimulation (PM-PU). The 2L-INT difference was > or = 0.6 ms in 10% of hands. PM-PU and D4M-D4U were > or = 0.5 ms in 56% and 77% of hands, respectively. The greater sensitivity of D4M-D4U might be explained by the funicular topography and consequent greater susceptibility to compression of the cutaneous fibers from the third interspace which, at the distal carpal tunnel, are clumped superficially in the anteroulnar portion of the median nerve just beneath the transverse ligament.

Action Potentials↗
PubMed1993

Physiological basis of voluntary activity inhibition induced by transcranial cortical stimulation.

Apart from exciting corticospinal cells and evoking a motor response, electrical or magnetic transcranial cortical stimulation (TCCS) delivered during voluntary activity produces a prolonged inhibition of activity, a silent period (SP), that can last up to 280 msec. The SP duration after TCCS is directly proportional to stimulus intensity. To determine the anatomic substrate and underlying physiological properties of the SP from TCCS, we (1) compared the SP from TCCS with the SP from cutaneous and mixed nerve stimulation, (2) studied the excitability cycle of spinal motor neurons in 3 double stimulus conditions: (a) after paired peripheral nerve stimulation, (b) after TCCS and peripheral nerve stimulation, and (c) after paired electrical TCCS, (3) investigated the timing of the excitability of the sensorimotor cortex measuring long latency responses from median nerve stimulation delivered inside the SP from TCCS. We found that after TCCS, spinal motor neuron segmental excitability is reduced for a period up to 100 msec. Inhibition at a suprasegmental, possibly cortical, level was even more prolonged for a period up to 160 msec, suggesting that at least the late part of the SP after TCCS is due to supraspinal inhibition. Determining the nature of the supraspinal inhibition such as the possible role of cortical inhibitory mechanisms may be useful in further understanding central mechanisms of voluntary motor control and sensorimotor processing.

Adult↗
PubMed1993

Sensitivity and specificity of diagnostic criteria for conduction block in chronic inflammatory demyelinating polyneuropathy.

Detection of conduction block (CB) has important clinical implications because it suggests segmental demyelination potentially reversible following treatment. There are no universally accepted criteria to define CB. We tested the sensitivity of two diagnostic criteria of partial motor CB in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and hereditary motor-sensory neuropathy type I (HMSN I) which are thought to be the prototypes of segmental and uniform demyelination respectively. Criterion I requires > 20% drop in negative peak amplitude and area and < 15% change in duration between proximal and distal compound muscle action potentials (CMAPs). Criterion II requires > 50% drop in negative peak amplitude and area of proximal CMAP independently from temporal dispersion. Twenty-eight percent of CIDP nerves and 65% of CIDP patients had CB according to criterion I. However, 29% of nerves and 61% of patients with HMSN I also fulfilled the same criterion. Thirty-four percent of CIDP nerves and 78% of CIDP patients and none of HMSN I patients fulfilled criterion II. Criterion II has the same sensitivity as criterion I, but seems to be highly specific in diagnosis of the segmental demyelination characteristic of CIDP. Therefore this criterion should be employed, as the diagnostic tool of CB, in chronic neuropathies presenting high stimulation threshold and coexisting axonal loss.

Action Potentials↗