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Biomedical subjects

S Scarpalezos

Publications and source records attributed to S Scarpalezos.

14 recordsLinked to original sources

Dystrophia myotonica. A model of combined neural and myopathic muscle atrophy.

Reports on clinical, electrophysiological and histological studies in dystrophia myotonica have shown that the peripheral nerves are usually not intact. In a few patients the neuropathy exceeds the myopathy. On the basis of these findings some authors believe that muscle changes in dystrophia myotonica are entirely due to the nerve lesions. However, despite the commonly found evidence of neuropathy, electromyographic and muscle biopsy findings are reported usually as "myopathic". Furthermore, clinical and laboratory findings indicate that the degree of muscle atrophy and peripheral nerve changes are unrelated. This report attempts to explain the discrepancies by suggesting that the "myopathic" and "neuropathic" changes in the muscle fibres in dystrophia myotonica are independent processes.

Action Potentials

F-wave studies on the deep peroneal nerve. Part 1. Control subjects.

An electrophysiological method is described for estimating the conduction velocity in the proximal segments (anterior horn cells to the knee) of the motor fibres of the deep peroneal nerve. The method utilizes large numbers of F-waves which are late muscle responses due to antidromically activated motoneurones. The results in 58 healthy subjects are presented. A detailed literature review concerning the nature of F-wave is presented.

Adolescent

F-wave studies on the deep peroneal nerve. Part 2.--1. Chronic renal failure 2. Limb-girdle muscular dystrophy.

The F-wave has been used for estimations of motor nerve conduction velocity (MNCV) along the proximal segment (anterior horn cells to the knee) of the axons of the deep peroneal nerve in patients with renal failure and limb-girdle muscular dystrophy. MNCV and terminal latencies with conventional methods have also been estimated. Patients with chronic renal failure show marked F-chronodispersion (i.e. F-wave temporal dispersion) and impaired conduction along proximal and distal segments of the deep peroneal nerve. There is no evidence of motor nerve impairment, with conventional and F-wave methods, in patients with limb-girdle muscular dystrophy. It is shown that F-wave measurements are useful in electrophysiological studies of patients and may be more sensitive than conventional MNCV methods.

Adolescent

The development of the extensor digitorium brevis muscle in progressive proximal muscular antrophies.

The development of the extensor digitorium brevis (EDB) muscle was studied in 39 healthy subjects, 27 patients with progressive proximal spinal muscular atrophy, 20 patients with limb-girdle muscular dystrophy and three with facioscapulohumeral muscular dystrophy. The EDB muscle is spared and usually hypertrophic in patients with muscular dystrophy, whereas it is often atrophic and weak in patients with spinal muscular atrophy. It is proposed that the degree of development of the EDB muscle can be used as a clinical sign in the differential diagnosis of progressive muscular atrophies.

Adolescent

[Radiological study of the cervical spinal column in some neurological degenerative diseases (author's transl)].

This study presents the findings from a neuroradiological investigation of the cervical spinal canal in a number of diseases of the nervous system. It concerns the measurement of the sagittal and transversal diameters of the spinal canal at levels C3 through C6. The material for this investigation was made up of two main groups: A) 400 controls and B) 110 patients. The second group consisted of the following: 1) 20 patients suffering from Friedreich's Ataxia, 2) 14 patients with Steinert's disease, 3) 44 patients with lateral amyotrophic sclerosis, 4) 14 patients suffering from Charcot-Marie-Tooth's disease, and 5) 18 patients with muscular dystrophy. The results are as follow: 1) In patients with Friedreich's Ataxia both the sagittal and transversal diameters are smaller than those of the controls. 2) On the contrary, in Charcot-Marie-Tooth's disease the sagittal diameter is larger than the controls. 3) The transversal diameter in patients with muscular dystrophy is smaller than the controls and 4) the sagittal diameter of the vertebral canal decreases from the top (C3) downwards (C6) while the transversal diameter increases.

Adult

Dystrophia myotonica. Peripheral nerve involvement and pathogenetic implications.

A comparative electrophysioloical study of patients with dystrophia myotonica and control subjects is presented. The study includes estimation of the number of motor axons innervating the extensor digitorum brevis muscle and measurements of the conduction of M- and F-waves along the deep peroneal nerve. There is unequivocal electrophysiological evidence of nerve involvement in the disease. This was indicated by (a) prolongation of the terminal latencies and slowing of the motor conduction of the deep peroneal nerve (P less than 0.001), (b) delayed conduction of the F-wave along the proximal segments of the nerves (P less than 0.02-0.01), (c) reduced number of motor axons innervating the extensor digitorum brevis muscle (P less than 0.001), (d) high amplitude motor unit potentials and discrete EMG activity on the maximal volitional contraction of minimally affected muscles in one patient. However, if the muscle changes were secondary to the nerve involvement occurring in the disease, one would expect that the electrophysiological findings of neuropathy would become more prominent in patients with severe muscle wasting and weakness. Our results showed that in some patients with marked muscle atrophy and weakness there was no evidence of nerve involvement while in other patients with slight to moderate degree of muscle weakness the electrophysiological studies indicated peripheral neuropathy. Therefore, it appears that both the nerves and the muscles are independently affected by the pleiotropic action of the responsible gene and the evidence does not suggest that the muscle atrophy of patients with dystrophia myotonica is entirely neural.

Adolescent

Muscular dystrophies and motoneuron diseases. A comparative electrophysiologic study.

Electrophysiologic investigations were carried out in 15 patients with limb-girdle muscular dystrophy, two patients with Becker's muscular dystrophy, and 22 patients with dystrophia myotonica. The results were compared with those obtained in 18 patients who had chronic progressive motoneuron disease and in 39 control subjects. These results were within normal limits in muscular dystrophies, with the exception of dystrophia myotonica, in which a neural disturbance is evident in the majority of patients. The results in motoneuron diseases were as expected for neurogenic disorders, loss of motor axons and compensatory increase of the amplitude of muscle potentials. There is no evidence of motoneuron dysfunction in muscular dystrophies, but in dystrophia myotonica, the muscles and nerves are affected independently by the pleiotropic gene of the disease.

Action Potentials

Skeletal mass conversions in hepatolenticular degeneration.

The influence of hepatolenticular degeneration, a hereditary disease, and the skeletal mass, has been studied in the present work by determining various parameters of the skeletal mass. As such, the results of the morphometric observation on the second left metacarpal have been considered. The results have shown: a significant decrease of the skeletal mass (osteoporosis), an increased innter diameter (d) which reveals an equally increased osteal absorption (osteolysis) and no connection of the sex, type and duration of the disease with the skeletal mass.

Adolescent

X-linked spinal and bulbar muscular atrophy of late onset. A separate type of motor neuron disease?

The clinical, electrophysiological and muscle biopsy findings of 7 cases with a peculiar form of X-linked hereditary degenerative motor neuron disease are presented. It is suggested that the disease might be a separate clinical entity with the following characteristics: (1) sex-linked recessive inheritance, (2) unusual but not invariable late onset, (3) slow progression, (4) facial-bulbar and proximal spinal muscle involvement, (5) consistent fasciculations, sometimes massive and more pronounced about the lips, chin and tongue, (6) fine tremor of the hands, (7) muscle cramps usually preceding the other symptoms, and (8) gynaecomastia as a frequent but not a constant feature.

Action Potentials

Sensory (1a) and F-wave conduction velocity in the proximal segment of the tibial nerve.

The F-wave was used to estimate the fastest motor nerve conduction velocity (MNCV) along the proximal segment (spinal cord to knee) of the axons of the tibial nerve in 65 control subjects, 8 patients with diabetic polyneuropathy, and 4 patients with Charcot-Marie-Tooth disease. Terminal latencies and MNCV along the distal segment (knee to ankle) of the nerve were also estimated with the conventional M-response technique. This article describes another method for estimating sensory nerve conduction velocity (SNCV) along 1a fibers of the tibial nerve for the spinal cord-to-knee segment. Proximal and distal MNCV showed moderate slowing in patients with diabetic polyneuropathy and severe slowing in those with Charcot-Marie-Tooth disease. In 17 control subjects, proximal MNCV for the axons supplying the abductor hallucis muscle was compared to that estimated for the axons to the gastrocnemius muscle. MNCV for the proximal is faster than that for the distal small muscle. In 2 patients, M- and F-responses were not obtained from the abductor hallucis; in these patients, effective estimation of the proximal MNCV was made from the gastrocnemius muscle and showed marked reduction.

Adolescent

F- and M-wave conduction velocity in amyotrophic lateral sclerosis.

The F-wave was used to estimate motor nerve conduction velocity (MNCV) along the proximal segment of the fastest axons of the deep peroneal nerve (anterior-horn cells to knee) in 13 patients with amyotrophic lateral sclerosis (ALS) and in 21 age- and sex-matched control subjects. Measurements were based on the shortest latency of 100 F-waves obtained after supramaximal stimulation at the ankle and knee. The MNCV was estimated with the F-wave and conventional M-response methods in the distal segment (knee to ankle) of the nerve. Our results showed that proximal-nerve conduction is faster than distal conduction both in control subjects and in ALS patients. In ALS, there was a moderate reduction of MNCV, which was of equal degree in both the proximal and distal segments of the deep peroneal nerve. In control subjects and in ALS patients, no statistically significant difference was found between the MNCV estimated for the knee-to-ankle segment by conventional means and that obtained by the F-wave method. This indicates that the F-wave of shortest latency is conducted by the fastest surviving motor fibers, as in the initial components of the M-response--demonstrating that it is legitimate to make direct comparison of F- and M-latencies in estimating the proximal MNCV.

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