摘要:

ABSTRACTThe compound muscle action potential and isometric twitch tension evoked by single and repetitive electrical stimuli are indicators of the number of motor units activated and of the contractile properties of the muscle. The action potentials and mechanical responses were recorded in proximal and distal muscles in patients with myeasthenia gravis and myopathy and compared with findings in normal subjects. In normal muscle, at low rates of stimulation (2‐3 s−1) the decrement was at most 5% in the action potential and 15‐24% in the twitch tension. Tetanic stimuli (50 s−1) were unsuitable for diagnostic purposes because of movement artefact.In patients with myasthenia gravis, the incidence and size of the decrement of evoked responses were greater in the platysma than in the elbow flexors and the adductor pollicis (ADP) muscles. The 2‐3 times greater post‐tetanic facilitation (PTF) of the action potential in the platysma than in extremity muscles also indicates a more severe functional block in facial muscle. The PTF is an indicator of recruitment of blocked fibres. The maximal decrement was grossly related to the titre of antibodies against the acetylcholine receptor. To reveal failure of neuromuscular transmission in patients with myasthenia gravis without a decrement, a small dose of d‐tubocurarine (0.2 mg in 30 ml of saline) was injected i.v. in the upper arm in a regional curare test. The sensitivity was greater in patients with myasthenia gravis than in controls and in patients with myopathy.Potentiation of twitch tension reflects contractile properties. In normal muscle twitch potentiation in the staircase (1‐3 s−1, 100 s in duration) and after tetanus (50 s−11.5 sin duration) was 2‐3 times greater in the platysma than in the elbow flexors and ADP, presumably related to the greater proportion of fast‐twitch fibers in facial muscle. The amplitude of the action potential and the twitch tension varied proportionally with the number of fibers activated and the difference in the decrements of the action potential and the twitch during the staircase in some patients with myasthenia gravis showed that the staircase phenomenon was diminished suggesting abnormalities in the excitation‐contraction coupling. The diminution of the staircase and post‐tetanic potentiation (PTP) in myopathy also indicates impairment of the excitation‐contraction coupling. In rats with severe chronic myasthenia gravis, the staircase and PTP were decreased even when the failing neuromuscular transmission was circumvented by applying direct stimuli to the extensor digitorum longus muscle (EDL). The abnormality in contractile properties was not reflected in the internal membranes as they appear in electronmicrographs of longitudinal sections of the muscle.During and after the staircase in the platysma and elbow flexors of normal subjects and in the fast‐twitch EDL of normal rat, the twitch tension was a function of processes with opposite effects on the mechanical response. The process that increased the twitch after a tetanus had two components with different time courses which were influenced differently by cooling and by Dantrolene Na. The process that diminished the twitch was related to fatigue. It is suggested that different myopathies may have different mechanisms associated with these processes

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04838.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe incidence and prevalence of motor neuron disease (MND) in the Province of Turin, North‐West Italy, were investigated for the period 1971‐1980. The crude incidence rate of MND was 0.67/100,000/year. The annual incidence rate, age and sex adjusted to the Italian population in 1971 was 0.69 cases per 100,000 inhabitants, 0.94 for men and 0.45 for women, with a male to female incidence ratio of 2.09:1. The prevalence of MND was 2.62/100,000, 3.57 for males and 1.71 for females. The mean age at the time of diagnosis was 55.6 years. Annual incidence rates increased with advancing age. Amyotrophic lateral sclerosis was found to be 4 times more frequent than progressive muscular atrophy (0.53/100,000/year v. 0.14/100,000/year). The distribution of MND was uneven in the Province suggesting a proportional relationship to the distribution of population density. Possible explanations of this finding are discus

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04839.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTAntibodies against skeletal muscle antigens and against thymic myoid cells were examined in sera from 40 patients with myasthenia gravis (MG). Using an indirect immunofluorescence technique, antibodies against the surface of muscle cells were found in 23 sera, and antibodies against muscle cell cross‐striations in 28 sera. Antibodies against thymic myoid cells were found in 27 sera, stained cells also occurring in fetal thymus from 14 weeks of gestation and in hyperplastic thymus from MG patients. Sera which stained myoid cells also stained muscle cell cross‐striations. Sera from all the 20 patients with thymoma contained antibodies to a citric acid extract of skeletal muscle (CAE) as detected by indirect haemagglutination, whereas sera from 20 comparable patients without thymoma did not contain CAE antibodies. The myoid cell antibodies could be absorbed by homogenized muscle, but not by CAE‐coated sheep erythrocytes. Different antibody patterns are seen among different MG patients; close associations were found between cross‐striational and myoid cell antibodies, and between CAE‐antibodies and

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04840.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTCerebrospinal fluid (CSF) from 40 multiple sclerosis (MS) patients was tested by solid‐phase radioimmunoasay (RIA) for ability to bind 2 common structural components of myelin and oligodendroglia, i.e., to bind myelin basic protein (MBP) and myelin‐associated glycoprotein (MAG). To prevent the effect of differences in CSF IgG concentration on binding activity, the CSF samples were tested at equal IgG concentration 1 mg/ml. The mean binding activity to MBP and MAG was significantly higher than in control neurotics, respectivelyP≤ 0.05 andP≤ 0.001. In 33% of MS cases, CSF antibody against both antigens was found. Indirect data were obtained that autoantibodies whose antigens are associated with myelinoligodendrocyte unit are produced locally within the central nervous system (CNS). Anti‐MAG and anti‐MBP CSF antibody activity was significantly higher,P≤ 0.01 for both antibody specificity, in MS cases characterized by high IgG Index, ≥ 0.70 =x+ SD in the neurotic group, versus MS cases characterized by normal IgG Index (≤ 0.70). Correlation coefficient between antibody activity and IgG Index values was 0.785 for anti‐MBP antibody, and 0.400 for anti‐MAG antibody. The importance of intrathecally produced antibody to MBP and MAG lies in the fact that it indicates an active humoral autoimmune process against a myelin‐oligodendrocyte unit in which more than one

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04841.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTA family with benign X‐linked muscular dystrophy (Becker type) has been studied. There was a total of 8 affected males, 7 of whom were alive. The clinical and pathological features are presented. The clinical symptoms started in the 2nd decade for most of the patients. The rate of progression was very slow and 3 patients became confined to a wheelchair in the second half of the 6th decad

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04842.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTAccuracy of echo‐encephalography (EVG) was assessed by comparison with computer‐tomography (CT) in a material of 49 children aged 2 weeks to 15.5 years and 158 adults aged 17 to 83 years. Third ventricle, width could be measured on EVG in all the patients, and the correlations with CF values were excellent both in children and adults (r= 0.89 andr= 0.94, respectively). Lateral ventricle echoes could be recorded in 43 children (87.7%) and in 95 adults (60.1%). There were very good correlations between lateral ventricle size estimated as LVI (lateral ventricle index on EVG) and BI (body index on CT) both in children and adults (r= 0.84 andr= 0.86, respectively). In adults, a fairly large proportion (46.3%) of the patients where lateral ventricle echoes could be recorded, apparently had essentially normal ventricle systems, although there was evidence that these echoes could be recorded more easily from widened ventric

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04843.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTSerum fatty acid compositions were determined in 21 Japanese patients with multiple sclerosis and 14 neurological controls. No statistical difference was found either for linoleic acid or for arachidonic acid between the 2 groups. It may be that neither serum linoleic acid nor arachidonic acid is inevitably associated with the pathogenesis of multiple sclerosis.

ISSN:0001-6314    

DOI:10.1111/j.1600-0404.1983.tb04844.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY