Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030552 (paresis)
 5,831 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of local cooling has been studied in 27 normal subjects, 8 cases of myotonia congenita, 5 of myotonic dystrophy and one of paramyotonia. Using the adductor pollicis we registered the compound muscle action potential, the isometric twitch force and the time to half relaxation, the maximum tetanic force and to time 3/4 relaxation. 1. In normal subjects the twitch force and maximum tetanic force decreased after cooling (Fig. 2). The amplitude of the action potential increased. 2. Myotonia congenita and myotonic dystrophy were not aggravated by cooling. Muscle force was reduced only in the same proportion as in normal subjects (Fig. 2). The myotonic after-contraction was made normal by cooling (Figs. 5 and 6). 3. In paramyotonia initial tonic stiffness with a pronouncedly prolonged twitch relaxation occured directly after cooling (Fig. 1 B). Paradoxical myotonia occured only after exercise and was accompained by increasing paresis (Figs. 3 and 8). The results indicate that exposure to cold has a specific effect on muscle function only in paramyotonia.
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PMID:Myotonia not aggravated by cooling. Force and relaxation of the adductor pollicis in normal subjects and in myotonia as compared to paramyotonia. 7 99

The maximum force of voluntary muscle contraction was registered under isometric conditions in nine patients with recessive myotonia congenita. The recordings were made on the upper arm. Five patients with severe myotonia had a transient weakness after muscle rest. Electromyographic registrations with wire electrodes showed that the myotonic muscle fiber discharges disappeared during the transient weakness. Medication improving myotonic stiffness also improved the weakness. The cause of transient weakness seems to be similar to that of myotonic stiffness. It is known that an increasing depolarization of the myotonic muscle fiber membrane leads to the myotonic discharges and myotonic stiffness. In severe myotonia the progressing depolarization could cause a loss of excitability of the muscle fiber membrane and thereby a transient paresis of a more or less large number of muscle fibers.
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PMID:Transient muscular weakness in severe recessive myotonia congenita. Improvement of isometric muscle force by drugs relieving myotomic stiffness. 8 Dec 74

This study reports on clinical and electromyographical findings which were obtained from an examination of male dizygotic twins and their father, who all suffered on a paramyotonia congenita. A simple coldness test can be used to distinguish paramyotonia congenita from myotonia congenita. Systematic cooling of the muscle of subjects with paramyotonia congenita leads to muscle stiffness and paresis, and finally to paralysis. An electromyographic analysis was carried out at various degrees of coldness. More than 300 paramyotonic series of discharges were analysed in respect to duration, amplitude and frequency. The results showed that the paramyotonic series are more similar to those of dystrophia myotonica than those of myotonia congenita.
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PMID:[Paramyotonia congenita: clinical and electromyographical tests (author's transl)]. 82 44

In order to study transient paresis, force and surface electromyograms (EMG) were recorded from the biceps brachii in 3 patients with recessive myotonia congenita, in 8 with myotonic dystrophy and in 3 controls. Epochs of 0.34 s EMG signal were stored every 0.44 s and processed to determine the integrated EMG (IEMG), the power spectrum and the average muscle fibre conduction velocity (MFCV). The protocol consisted of 5 maximal voluntary contractions lasting 10.3 s and 13 s recovery. During the first 1-1.5 s the MFCV and median frequency (Fmed) of the power spectra of the controls increased (mean increase 12.5% and 14%, respectively) in all 5 consecutive contractions. Subsequently, MFCV, Fmed and force declined as a consequence of fatigue. Both the initial force and MFCV declined with successive contractions. The results in myotonic dystrophy were not different from the controls, except that the changes during fatigue were far less pronounced. These events are the reverse of the changes found in myotonia congenita in which an initial loss of force (maximal by 61-79%) and a decline of the IEMG (maximal by 79-92%) was found during the first contraction. This transient paresis was accompanied by a dramatic fall in the MFCV concomitant with a shift of the power spectrum to the lower frequencies. The first MFCV measurement of the 5 contractions was always normal. The decline in MFCV was maximal after 1.5-2.5 s and varied for the 3 patients from 32-52%. In general, the decline in force, IEMG and MFCV lessened with each successive contraction (warming-up phenomenon), though sudden deteriorations were sometimes observed during later contractions. The same results were found for brachioradialis and abductor digiti minimi. The results provide evidence that transient paresis is of clinical relevance in myotonia congenita and that it is caused by alterations in the muscle membrane. These membrane changes result in a strong decline of the muscle action potential conduction velocity and consequent depolarization block of the muscle fibres. Our method did not show the presence of transient paresis during voluntary contraction in myotonic dystrophy.
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PMID:Transient paresis in myotonic syndromes. A surface EMG study. 273 Oct 26

Botulinum toxin (BT) is a potent local muscle relaxant with analgetic properties. Myotonia congenita (MC) is a genetic disorder producing muscle rigidity and pain. BT injected into the trapezius produced mild paresis, but no effect on rigidity and pain. There were no signs of systemic effects. Lack of BT efficacy on MC rigidity confirms its origin from muscle membrane dysfunction rather than from inappropriate neuromuscular activation. Lack of BT efficacy on pain could be caused by lack of anti-rigidity effect. It could also be due to separate non-muscular pain mechanisms unresponsive to BT.
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PMID:Botulinum toxin in myotonia congenita: it does not help against rigidity and pain. 2435 52