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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study of 7 cases of Charcot-Marie-Tooth disease associated with a dyskinesia resembling benign essential tremor is presented. In 4 patients, the family history strongly suggested an autosomal mode of transmission, 2 cases were sporadic without an established genetic pattern and 1 was probably recessive. The distal parts of the upper and lower limbs showed imparied muscle strength with slight or no atrophy in 4 patients and conspicuous weakness and wasting in another 2. One patient was a chairbound. Although essential tremor and the tremor seen in these patients are clinically (phenotypically) similar it seems possible that they result from two different genotypes. Further, it seems that cases with Charcot-Marie-Tooth disease and "essential tremor" are not the result of the association of two separate dominant characteristics which are generally inherited as mendelian dominant traits. In spite of the diversity of the clinical manifestations of the peripheral neuropathy, the semiologically different types of essential tremor and the electrophysiological data, it is concluded that patients who develop a peripheral neuropathy on a familial basis and who exhibit clinical features of similar character, suffer from a common type of pathological disorder. Stress is laid upon the fact that Friedreich's ataxia and Charcot-Marie-Tooth disease share many clinical features. It is suggested that when Friedreich's ataxia and Charcot-Marie-Tooth disease seem to be present in the same individual and/or alternate in different members of the same family, the process is likely to be one of Charcot-Marie-Tooth disease. The value of the type of inheritance, natural history, clinical examination and electrophysiological data in differentiating Charcot-Marie-Tooth disease (with or without essential tremor) from other degenerative disorders is analyzed.
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PMID:Charcot-Marie-Tooth disease associated with "essential tremor": Report of 7 cases and a review of the literature. 93 72

Much confusion and disagreement exists regarding the classification and characteristics of inherited disorders manifesting neurogenic muscular atrophy. Many authors consider Charcot-Marie-Tooth syndrome (CMTS) and Roussy Levy syndrome (RLS) forme fruste or variants of Friedreich's ataxia (FA). Familial kyphoscoliosis has often been described in FA and RLS but not with CMTS. The purpose of this paper is to present detailed clinical and laboratory findings in a family with three cases of Scheuermann's kyphoscoliosis and CMTS in three generations. In all cases Scheuermann's kyphoscoliosis was associated with pes cavus, markedly diminished vibratory and position sensation in the lower extremities, absent deep tendon reflexes and muscular atrophy, predominantly of the distal muscles. Fine rhythmic tremor of outstretched hands and positive Romberg sign were present in one case only. Serum creating phosphokinase was elevated in two cases. Motor nerve conduction studies revealed impaired function in the median, ulnar, tibial and peroneal nerves. Sensory nerve conduction wal also impaired in median and ulnar nerves. There was evidence of left ventricular hypertrophy in one case only. The nosology and relationship between CMTS, RLS and FA are discussed.
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PMID:Scheuermann's kyphoscoliosis associated with Charcot-Marie-Tooth syndrome. 94 37

The patients belonged to three different families and were products of consanguineous marriage. The neurological symptoms and signs in these patients began in infancy or childhood and included gait disturbance, horizontal nystagmus, distention tremor of the hands, muscular wasting and sensory impairment of the hands and legs. CT-scan and/or MRI showed atrophy of the cerebellum. Serum biochemical analyses revealed hypoalbuminemia with hyperlipidemia. There were no abnormalities in the heart, liver, kidney, gastrointestinal tract, or endocrine systems. The autopsy revealed degenerative changes in the spinal cord including posterior column and lateral pyramidal tract, as well as in the peripheral nerves and cerebellar cortex. Although we have speculated that the disease presented here would be a clinical variants of Friedreich's disease, it would make a new clinical entity because there was no report about the association to hypoalbuminemia and hyperlipidemia with spinocerebellar degeneration.
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PMID:[A hereditary ataxia associated with hypoalbuminemia and hyperlipidemia--a variant form of Friedreich's disease or a new clinical entity?]. 129 49

Control of isometric forces during grasping or handling of objects is an essential feature of all skilled manual performances. Previous studies of hand function in cerebellar patients were restricted to movements; force control was only investigated under isotonic conditions in combination with movements. Control of isometric forces during voluntary contraction of finger muscles was investigated in 31 patients with chronic cerebellar disease and in 20 normal controls. Eight patients with Friedreich's ataxia were considered to be typical for a disease affecting the afferents to the cerebellum; 4 patients with anterior lobe atrophy, which affects leg movements to a greater extent than finger movements, were compared with 3 patients with hemisphere lesions; 16 patients suffered from diffuse cerebellar atrophy. Using a recently developed microcomputer system for the continuous measurement of finger force, control of isometric force was studied in several tasks within the same subjects. The tasks included the maintenance of constant force output at different force levels with and without visual feedback, fast repetitive force changes, tracking of a sinusoidal target presented visually, and measurement of maximum grip force. The amount of voluntary contraction in terms of muscular power was normal in all patients; in all other tasks clear deficits were observed. The extent of the disturbances was highly variable between patients even within the same clinical subgroup. The detailed analysis of force traces revealed a great variety in types of disturbance. The frequently observed slowing of the speed in repetitive force changes can be attributed to different components in different patients and not only to difficulties at turning points as might be predicted from comparable movement studies. In addition, performance deficits across different tasks were not uniform, indicating dissociation of impairment. Deficits in maintaining force, which may be interpreted as dysmetria or due to tremor, do not necessarily imply an abnormality in diadochokinesis, as measured in fast repetitive force changes, nor does the converse apply.
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PMID:Control of isometric finger force in patients with cerebellar disease. 317 93

Sudden tilting of a platform around the axis of the human ankle joint causes a regular pattern of short and medium latency EMG responses in the stretched triceps surae muscle and a long latency response in its antagonist, the anterior tibial muscle. This paper reports alterations of these EMG responses in 41 patients with cerebellar lesions. Patients with anterior lobe atrophy exhibited normal latencies of all EMG responses, but an increase in duration and amplitude of the long latency response. This may at least partially explain the 3 Hz postural tremor, which can be evoked in these patients through a toe-up tilt of the platform. Patients with lesions restricted to the vestibulocerebellum and to the cerebellar hemispheres exhibited normal latencies of all EMG responses. The most specific finding in all of the patients suffering from Friedreich's ataxia (affecting spinal afferents) was the massive delay of the stabilising response of the anterior tibial muscle. The fact that the patients with lesions restricted to the cerebellum invariably exhibited normal latencies of postural "reflexes" indicates that the exact "timing" of these responses is independent of the cerebellum. The duration and amplitude of the long latency response of the antagonist, however, seems to be controlled by the cerebellum.
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PMID:Characteristic alterations of long-loop "reflexes" in patients with Friedreich's disease and late atrophy of the cerebellar anterior lobe. 674 44

Hexosaminidase deficiency diseases or GM2-gangliosidoses were originally described as infantile encephalopathies. Recently, hexosaminidase deficiencies have been found with different phenotypes, including juvenile and adult encephalopathies, cerebellar ataxias, and motor neuron diseases. Individual cases have resembled Ramsey-Hunt syndrome, olivopontocerebellar ataxia, Friedreich ataxia, amyotrophic lateral sclerosis, Kugelberg-Welander disease, Fazio-Londe disease, and Charcot-Marie-Tooth disease. Tremor, dystonia, spastic paresis, and psychosis have been seen. Since few diagnosable causes for these system atrophies are known, these patients should be tested for hexosaminidase deficiency. These recessive disorders fit a multiple loci/multiple alleles genetic scheme, and a clinical genetic classification is presented.
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PMID:The clinical spectrum of hexosaminidase deficiency diseases. 719 92

This paper reviews the features and topodiagnostical meaning of pathological body posture in cerebellar disorders and presents knowledge as to the physiology and pathophysiology of postural disturbances attributed to the cerebellum. Lesions of the spinocerebellar (upper vermal and intermediate) part of the anterior lobe lead to spontaneous anterior-posterior body sway, with a frequency of about 3 Hz with mild or absent ataxia of the upper limbs, but prominent ataxia of the lower limbs. The tremor is provoked by eye closure and by body displacement. Increased gain and poor cerebellar control of the duration and gain of stabilizing reflexes may be the mechanisms of this oscillation. Lesions of the lower (vestibulocerebellar) vermis cause postural ataxia of the head and trunk while sitting, standing, and walking. Postural ataxia is omnidirectional, sometimes of excessive amplitude and contains frequency components below 1 Hz. Dysmetria of the upper and lower limbs is not prominent. Visual stabilization is less than in the other groups of cerebellar patients. Lesions of the cerebellar hemispheres alone, do not cause an increase of postural sway. Lesions of spinocerebellar afferents (Friedreich's disease) lead to a low frequency large amplitude lateral sway with the most of its power below 1.1 Hz. Visual stabilization is preserved. Latencies of early and late EMG responses to sudden displacements are normal in patients with cerebellar disorders. The cerebellum is, therefore, unlikely to be the primary generator of these reflexive responses. On the other hand, the temporal composition of the orderly time sequence of a complex motor program--be it a voluntary act or its postural balancing--is deranged in cerebellar lesions. It is hypothesized that the cerebellum helps to coordinate the timing not only within but also between the single components involved in each subunit of a complex movement in three-dimensional space and that is scales the size and duration of each muscular action. The cerebellum possibly specifies the cortical movement command and sends it back to the motor cortex. The basic structure of a motor program, however, does not seem to be generated within the cerebellum.
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PMID:Compartmentalized cerebellar functions upon the stabilization of body posture. 809 Oct 78

Developments in the field of Huntington's disease have focused on the potential benefits of predictive testing. Markers have been described for autosomal dominant cerebellar ataxia and for certain subtypes of Friedrich's ataxia. Argentophilic neuronal and glial inclusions appear to be the first specific pathologic hallmark of multiple system atrophy. "Pure" hereditary spastic paraplegia is not a multisystem disorder of the central nervous system, but a monomorphic and stereotyped disease. Advances in Tourette's syndrome are limited because the presumed gene eludes identification. A new type of myoclonus, propiospinal myoclonus, has been described. Clinical and electrophysiologic criteria for defining primary orthostatic tremor have been proposed. Understanding of the neurophysiologic substrate of essential tremor and myoclonus is improving. New neurologic disorders presenting clinically with prominent movement disorder continue to be described.
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PMID:Choreas, hereditary and other ataxias, tics, myoclonus, and other movement disorders. 850 6

Molecular genetics is currently the most powerful tool for studying hereditary diseases of the central nervous system: Huntington's disease, dopa-nonresponsive dystonia, Friedreich's disease, etc. The review presents the most important results obtained in this field by the Department of Neurogenetics, Institute of Neurology, in collaboration with several Russian and foreign research institutes. The authors were the first to perform a molecular analysis of mutations and haplotypes in Huntington's disease, dopa-nonresponsive dystonia, Wilson's disease and studied the frequencies of various mutations and main genotype-phenotype correlations in the Russian population. The first direct diagnosis of Huntington's disease in Russia, as well as indirect diagnosis of Friedreich's disease, dopa-nonresponsive dystonia and Wilson's disease have been made. The authors began to investigate trinucleotide repeat expansion in dominant spinocerebellar ataxias and related disorders. The Department of Neurogenetics collected a valuable bank of DNA samples, which is sufficient to perform linkage analysis in essential tremor, novel forms of congenital cerebellar atrophy and progressive muscular atrophy.
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PMID:[Molecular genetic analysis--a new stage in the study of hereditary diseases of the central nervous system]. 875 71

Movement disorders are well known features of some dominant hereditary ataxias (HA), specially SCA3/Machado-Joseph disease and dentatorubropallidolusyan atrophy. However, little is known about the existence and classification of movement disorders in other dominant and recessive ataxias. We prospectively studied the presence of movement disorders in patients referred for HA over the last 3 years. Only those patients with a confirmed family history of ataxia were included. We studied 84 cases of HA, including 46 cases of recessive and 38 cases of dominant HA. Thirty out of 46 cases of recessive HA could be classified as: Friedreich ataxia (FA), 29 cases; vitamin E deficiency, 1 case. Twenty-three out of 38 cases of dominant HA could be classified as: SCA 2, 4 cases; SCA 3, 8 cases; SCA 6, 4 cases; SCA 7, 6 cases and SCA 8, 1 case. We observed movement disorders in 20/38 (52%) patients with dominant HA and 25/46 (54%) cases with recessive HA, including 16 patients (16/29) with FA. In general, postural tremor was the most frequent observed movement disorder (27 cases), followed by dystonia (22 cases). Five patients had akinetic rigid syndrome, and in 13 cases, several movement disorders coexisted. Movement disorders are frequent findings in HA, not only in dominant HA but also in recessive HA.
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PMID:Movement disorders in hereditary ataxias. 1222 Jun 93


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