Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Forty-five African children with SMA were seen over a period of five years. Fifteen had severe infantile form (Group 1), 19 intermediate (Group 2), 9 juvenile (Group 3) and 2 cervical type. A positive family history was obtained in only 9% of patients. The female/male ratio was 1:1.7. The age of onset was under four months in Group 1, between 5-24 months in Group 2. In 77% of Group 3 onset was between 5-24 months, 22% between 25-48 months. The lower limbs were more severely affected than upper limbs in all except the two patients with cervical SMA, proximal muscles more than distal in 82% and proximal and distal muscle were equally affected in 18%. Bulbar weakness was present in 73% and facial weakness in 80% of Group 1 patients only. Fasciculation of tongue occurred in 50% of Group 1, 42% of Group 2 and 44% of Group 3 patients. Tremor of hands was seen in none of the patients in Group 1, 58% in Group 2 and 66% in Group 3. Tendon reflexes were absent or depressed in all except one patient in Group 2 and were normal in the legs of the two patients with cervical SMA. The blood CK was elevated in 26% of patients. An ECG "tremor" was present in 26% of patients in Group 1, 68% in Group 2 and 66% in Group 3. Four patients (all in Group 1) died of pneumonia; the outcome in the others is not known.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Spinal muscular atrophy in African children. 231 55

Brain regions involved in tremor and voluntary movement were compared in seven subjects with hemiparkinsonian tremor using positron emission tomography and the [15O] water bolus activation method. Repeated measurements of the regional cerebral blood flow were performed both before and after tremor arrest induced by administration of L-dopa as well as during voluntary repetitive movements of the hand contralateral to tremor side. The normalized regional cerebral blood flow (NrCBF) was measured in regions of interest with anatomical boundaries that were defined for each subject by means of a three-dimensional reconstruction of magnetic resonance imaging data. Taking the rest after L-dopa as a control condition, NrCBF increased during tremor in a network of regions including the precentral (mean +/- SD 5.36 +/- 4.6%, P = 0.006) and paracentral (6.11 +/- 6%, P = 0.01) gyri contralateral to tremor side, the supplementary motor area (SMA; 4.03 +/- 4%, P = 0.02, n = 8 pairs), and the cerebellar vermis (8.64 +/- 9.9%, P = 0.01, n = 12). During voluntary repetitive movement of the hand contralateral to tremor compared with rest after L-dopa, the same patients activated the precentral (8.25 +/- 2.6%, P = 0.0006) and postcentral regions contralateral to movement (8.43 +/- 3.7%, P = 0.002), and the cerebellar cortex (3.49 +/- 2.1%, P = 0.03), precentral (3.58 +/- 3.1%, P = 0.04), and paracentral (4.03 +/- 3.6%, P = 0.04) regions ipsilateral to movement. The cerebellar vermis was activated (8.15 +/- 5.6%, P = 0.02, n = 8) as well as the SMA, but not significantly at the 0.05 level (5.16 +/- 5%, P = 0.08, n = 5). These results confirm the similarities of brain structures involved in parkinsonian tremor and voluntary movement and provide an anatomofunctional substrate for their clinical interactions.
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PMID:Tremor and voluntary repetitive movement in Parkinson's disease: comparison before and after L-dopa with positron emission tomography. 882 85

Three type III spinal muscular atrophy (SMA) families are described in which the same deletion pattern for SMN gene and flanking loci is apparent in both affected and unaffected siblings. Deletions extending to include the NAIP gene are reported in one sibship. All three individuals in which SMN and/or NAIP deletions were detected showed the same haplotypes for SMA linked microsatellite markers as their affected sibs. The three index cases had a SMA III with early onset (1.5-2 yr) and became chairbound at the age 4, 5 and 20 yr. The three haploidentical sibs were given a clinical severity score. One of them showed no sign of the disease at the age of 4 yr and was considered "unaffected"; a 35-yr-old female, who had no symptoms but showed tongue fasciculations and hand tremor was considered "asymptomatic"; a 34-yr-old female, who had mild muscular weakness since the age of 24, was rated "mild". These observations demonstrate the presence of a continuum of clinical variability within SMA III families. These data suggest that, in these three families at least, the SMA phenotype is caused or influenced by another gene(s) additional to SMN.
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PMID:Discordant clinical outcome in type III spinal muscular atrophy sibships showing the same deletion pattern. 888 55

The history of the spinal muscular atrophies (SMA) began in the 1890s with Guido Werdnig and Johann Hoffmann. Together, their papers present a rather complete picture of the clinical and pathologic aspects of infantile SMA: onset during the first year of life, occurrence in siblings with normal parents, progressive floppiness and weakness, hand tremor, and death from pneumonia in early childhood. Based on the work of an international collaboration, the following is current nomenclature: SMA type 1 (or I) for onset of symptoms before age 6 months, SMA type 2 (II) for onset between 6 and 18 months, and SMA type 3 (III) for onset after age 18 months. Linkage of autosomal recessive SMA to chromosome 5q11.2-13.3 was reported by Gilliam et al in 1990. A novel gene, whose function remains unknown, called the survival motor neuron gene (SMN) at 5q13, contains deletions in more than 98% of SMA patients. Some patients with atypical forms of SMA have been shown to have mutations in SMN. Because there is no effective therapy for SMA, management consists of preventing or treating the complications of severe weakness, such as restrictive lung disease, poor nutrition, orthopedic deformities, immobility, and psychosocial problems.
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PMID:Spinal muscular atrophy. 956 64

We report the case of a man who had an insidious onset of asymmetrical distal muscle weakness of the upper extremity at the age of 17. Objective findings were 1) muscular atrophy of calf and forearm flexor muscles and intrinsic hand muscles; 2) fasciculations; and 3) hand tremor. EMG and muscle biopsy showed neurogenic changes. MRI of the medulla and plasma creatine kinase were normal. Genetic testing for SMA-III was negative.
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PMID:[Juvenile asymmetrical segmental spinal muscular atrophy]. 1222 8

Data from experiments in MPTP monkeys as well as from invasive and non-invasive recordings in patients with Parkinson's disease suggest an abnormal synchronization of neuronal activity in the generation of resting tremor in Parkinson's disease. In six patients with tremor-dominant idiopathic Parkinson's disease, we recorded simultaneously surface electromyograms (EMGs) of hand muscles, and brain activity with a whole-head magnetoencephalography (MEG) system. Using a recently developed analysis tool (Dynamic Imaging of Coherent Sources; DICS), we determined cerebro-muscular and cerebro-cerebral coherence as well as the partial coherence between cerebral areas and muscle, and localized coherent sources within the individual MRI scans. The phase lag between the EMG and cerebral activity was determined by means of a Hilbert transform of both signals. After overnight withdrawal from medication, patients showed typical Parkinson's disease resting tremor (4-6 Hz). This tremor was associated with strong coherence between the EMG of forearm muscles and activity in the contralateral primary motor cortex (M1) at tremor frequency but also at double tremor frequency. Phase lags between M1 activity and EMG were between 15 and 25 ms (M1 activity leading) at single, but also at double tremor frequency, corresponding well to the corticomuscular conduction time. Furthermore, significant coherence was observed between M1 and medial wall areas (cingulate/supplementary motor area; CMA/SMA), lateral premotor cortex (PM), diencephalon, secondary somatosensory cortex (SII), posterior parietal cortex (PPC) and the contralateral cerebellum at single tremor and, even stronger at double tremor frequency. Spectra of coherence between thalamic activity and cerebellum as well as several brain areas revealed additional broad peaks around 20 Hz. Power spectral analysis of activity in all central areas indicated the strongest frequency components at double tremor frequency. Partial coherence analysis and the calculation of phase shifts revealed a strong bidirectional coupling between the EMG and diencephalic activity and a direct afferent coupling between the EMG and SII and the PPC. In contrast, the cerebellum, SMA/CMA and PM show little evidence for direct coupling with the peripheral EMG but seem to be connected with the periphery via other cerebral areas (e.g. M1). In summary, our results demonstrate tremor-related oscillatory activity within a cerebral network, with abnormal coupling in a cerebello-diencephalic-cortical loop and cortical motor (M1, SMA/CMA, PM) and sensory (SII, PPC) areas contralateral to the tremor hand. The main frequency of cerebro-cerebral coupling corresponds to double the tremor frequency.
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PMID:The cerebral oscillatory network of parkinsonian resting tremor. 1247 7

Whole-head MEG-systems and modern spatial-filter-based analysis tools recently provided new possibilities to analyze non-invasively cerebral networks of human tremor syndromes. We compared tremor syndromes in Parkinsonian patients with a typical resting tremor as well as in patients with hepatic encephalopathy (HE) with a postural tremor called "mini-asterixis". In 6 patients with idiopathic Parkinson's disease (PD) we found strong coherence between the electromyography (EMG) of forearm muscles and activity in the contralateral primary motor cortex (M1) at tremor frequency but also at double tremor frequency. Furthermore, significant coherences were observed between M1 and medial wall areas (CMA/SMA), lateral premotor cortex, diencephalon, SII cortex, posterior parietal cortex and the contralateral cerebellum at tremor and, stronger, at double tremor frequency. In contrast, in 6 patients with "mini-asterixis" and HE due to chronic liver cirrhosis excessive corticomuscular coherence occurred at the individual tremor frequency between EMG and M1 activity. Interestingly, thalamus-M1 coupling was significantly altered towards lower frequencies matching the individual frequency of the mini-asterixis. Cerebro-muscular or cerebro-cerebral coupling at double tremor frequency was not observed. Therefore, "mini-asterixis" reflects most likely a pathologically decelerated and augmented synchronized rhythmical motor cortical output. This could be due to functional alterations in the M1-basal-ganglia-thalamo-cortical loops in severe HE. In summary, tremor syndromes in PD as well as in patients with HE and "mini-asterixis" are characterized by pathological oscillatory activity within cerebral networks of motor areas. However, the present study shows different mechanisms of tremor generation in PD and HE patients.
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PMID:Pathological oscillatory coupling within the human motor system in different tremor syndromes as revealed by magnetoencephalography. 1601 24

Common neurological manifestation of Wilson's disease (WD) is a postural tremor of the upper extremities. Recently, the primary sensorimotor cortex (S1/M1) has been shown to be involved in WD postural tremor generation. However, neuropathological changes in WD are mostly observed in subcortical structures. We therefore aimed to investigate whether S1/M1 may be functionally interconnected with other brain areas. In five WD patients, we used magnetoencephalography and surface electromyography (EMG) to record simultaneously cerebral neuronal activity and muscular activity during sustained posture of the right forearm. As demonstrated previously, the strongest coupling to tremor EMG was observed in the contralateral S1/M1. This area was taken as reference in order to identify and localize cerebro-cerebral coherence at tremor frequency and its first harmonic. The analysis revealed significant coherence within an oscillatory network including S1/M1, higher cortical motor areas (premotor cortex, PM; supplementary motor area, SMA), posterior parietal cortex (PPC) and thalamus contralateral as well as the cerebellum ipsilateral to the tremor forearm. Flow of information was mainly of bidirectional nature. Taken together, our results indicate that WD postural tremor is generated within a synchronized cerebello-thalamo-cortical network, comprising S1/M1, higher cortical motor areas (SMA, PM), and PPC.
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PMID:Synchronized brain network underlying postural tremor in Wilson's disease. 1699 Nov 50

We treated a patient with levodopa-resistant akinesia with motor cortex stimulation (MCS), and she showed dramatic improvement more than 1 year. On admission, the patient presented severe akinesia and gait disturbance without tremor and rigidity, and did not respond to levodopa test. The patient was suspected pure akinesia and progressive supranuclear palsy. First, high-frequency rTMS of primary motor cortex was examined, and showed the dramatic improvement. Next, chronic subdural electrodes were implanted over the motor cortex bilaterally. One year after surgery, the Unified Parkinson's Disease Rating Scale had improved remarkably, and she could walk four times faster than before. The H2 15O PET study showed a significant increase of rCBF in the left SMA and right dorsolateral prefrontal cortex after bilateral MCS. MCS may be an alternative treatment for patients with akinesia, including those with PD, and particularly for levodopa-resistant patients, who respond well to rTMS.
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PMID:Motor cortex stimulation for levodopa-resistant akinesia: case report. 1755 43

Parkinson's disease (PD) is associated with abnormal hypersynchronicity in basal ganglia-thalamo-cortical loops. The clinical effectiveness of subthalamic nucleus (STN) high frequency stimulation indicates a crucial role of this nucleus within the affected motor networks in PD. Here we investigate alterations in the functional connectivity (FC) profile of the STN using resting state BOLD correlations on a voxel-by-voxel basis in functional magnetic resonance imaging (fMRI). We compared early stage PD patients (n=31) during the medication-off state with healthy controls (n=44). The analysis revealed increased FC between the STN and cortical motor areas (BA 4 and 6) in PD patients in accordance with electrophysiological studies. Moreover, FC analysis of the primary motor cortex (M1) hand area revealed that the FC increase was primarily found in the STN area within the basal ganglia. These findings are in good agreement with recent experimental data, suggesting that an increased STN-motor cortex synchronicity mediated via the so called hyperdirect motor cortex-subthalamic pathway might play a fundamental role in the pathophysiology of PD. An additional subgroup analysis was performed according to the presence (n=16) or absence (n=15) of tremor in patients. Compared to healthy controls tremor patients showed increased STN FC specifically in the hand area of M1 and the primary sensory cortex. In non-tremor patients, increased FC values were also found between the STN and midline cortical motor areas including the SMA. Taken together our results underline the importance of the STN as a key node for the modulation of BG-cortical motor network activity in PD patients.
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PMID:Resting state fMRI reveals increased subthalamic nucleus-motor cortex connectivity in Parkinson's disease. 2125 61


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