Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-eight cases of mirror writing were seen during a period of three and a half years. These consisted of 12 patients with essential tremor, nine with Parkinson's disease, three with spino-cerebellar degeneration and four other cases. There were no cases of hemiparesis, aphasia, apraxia, agnosia or confusion. Fragmentary reversals were excluded from this study. Since essential tremor, Parkinsonian tremor and cerebellar tremor can be abolished by a stereotaxic produce applied to the thalamus, a common neural pathway via the thalamic nuclei may exist in these disorders. The existence is therefore proposed of some neural mechanism that controls the higher cerebral function of writing via the thalamus.
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PMID:The aetiology of mirror writing: a new hypothesis. 343 91

Nine parkinsonian patients were studied during one night using the static charge sensitive bed (SCSB) method for the monitoring of respiration, ballistocardiogram (BCG) and body movements. The parkinsonian sleep was more restless than that of the controls. As the SCSB-defined levels of autonomic nervous activity were concerned, the amount of motor active wakefulness (MAW) was significantly (P less than 0.05) increased in parkinsonian patients, who also had less quiet sleep (P less than 0.05) than the controls. Parkinsonian tremor was present during 29.8 +/- 15.8% of the time in bed. Usually it was observed during wakefulness; it disappeared when the patient fell asleep. The frequency of turning-over events in bed was smaller in the parkinsonian patients than in the controls (P less than 0.05). When the heart rate changes associated with sleep movements were studied it was found that the parasympathetic deceleration component in the parkinsonian patients was absent. The motor dysfunction associated with Parkinson's disease is reflected in many ways in the sleep movement activity. Sleep disturbances in PD seem to be secondary in character; i.e. they can be due to impaired motor functions like turning around in the bed, or due to impaired arousal mechanisms during sleep.
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PMID:Sleep movements and associated autonomic nervous activities in patients with Parkinson's disease. 363 Jun 47

Dysfunction of neurons in the extrapyramidal system (EPS) which use GABA as their neurotransmitter can be noted in both degenerative diseases of the EPS and in iatrogenic (i.e. drug-induced)disorders of EPS function. In Huntington's chorea there is a loss of both GABA neurons and GABA receptors in the striatum; those remaining GABA receptors likely have an altered kinetic profile, with a higher affinity for GABA than the receptors found in the non-Huntington's brain. In Parkinson's disease the lower levels of L-glutamic acid decarboxylase observed in the EPS is likely not associated with neuronal cell loss but is likely secondary to the dopamine neuron loss. These alterations in GABA neuron function and the long-term changes associated with chronic L-DOPA therapy may be related to Parkinsonian tremor. The drug-induced dyskinesias (L-DOPA, neuroleptic) appear to be associated with a relative hypo-function of EPS GABA neurons, especially in relation to DA neuron function, whereas in the case of drug-induced Parkinsonism the opposite may be the case. The function and dysfunction of GABA neurons in the EPS cannot be seen as a separate entity, but must be considered in relation to alterations in other EPS neurons, especially dopamine and acetylcholine.
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PMID:The neuropathology of GABA neurons in extrapyramidal disorders. 644 16

The effects of a muscle twitch on the tremor of the extensor indicis muscle and of the tibial anterior muscle have been recorded in 14 patients with essential tremor and in 10 patients with Parkinson's disease. The muscle twitch evoked by the electrical stimulation of the motor nerve inhibits the tremor and synchronises it. The mean duration of the inhibition is 92.1 +/- 6.8 ms for essential tremor and 183.0 +/- 16.8 ms for Parkinsonian tremor. This inhibitory phase lasts longer when the muscle twitch is induced during the second half of the Parkinsonian tremor cycle. The effects of voluntary contraction and of unloading suggest that inhibition and resetting of the tremor can be attributed to the autogenic mechanism induced by Ib fibres discharges. The presence of a rhythmic inhibition in the cycle of Parkinsonian tremor accounts for the longer duration of the inhibitory phase. In practice, these techniques aid the diagnosis of tremor in these two conditions, for example they assist the identification of low frequency essential tremor and of postural tremor in Parkinson's disease.
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PMID:Inhibition and synchronisation of tremor induced by a muscle twitch. 743 Oct 32

The author summarises the various origins of hand tremor. Physiologic tremor can be demonstrated in any individual. This tremor is normally recordable at a stable frequency of 8-10 Hz, though this can be influenced by age, the amplitude can vary substantially. Physiological tremor is believed to have its origin in the mechanical properties of the extremities, and the firing properties of motoneurones. Essential tremor is an inherited autosomally dominant phenomenon, and is characterised by action and postural tremor. It is progressive with age. The use of low doses of theophylline in the treatment of essential tremor is emphasised, in view of the low incidence of side effects. A hypothesis is also presented to account for essential tremor in terms of an imbalance in the activity of excitatory and inhibitory amino acid system. Parkinsonian tremor may begin as postural or resting tremor on one side, and it is reduced by active movement of the affected extremity. The prognosis of Parkinson's disease presenting with tremor is better when presenting with hypokinesia. The increasing use of non-specific drugs in the treatment of Parkinsonism, and the use of thalamic high frequency stimulation are indicated.
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PMID:[Most frequent causes for hand tremor in clinical practice]. 747 62

We report our experience with lidocaine microinjection into the thalamus in 10 patients undergoing stereotactic thalamotomy for the treatment of Parkinsonian or non-Parkinsonian tremor. 18 injection sites in 4 patients with Parkinson's disease and 22 sites in 6 patients with other forms of tremor have been compared with respect to the effect of microstimulation. In over two thirds of cases the test microinjection replicated the effects of microstimulation. Long term follow up will be required to determine whether lesions made on the basis of lidocaine induced tremor suppression will result in a lower rate of tremor recurrence than those based on stimulation induced tremor suppression. In those patients in whom stimulation induced tremor suppression occurs but tremor arrest cannot be produced with lidocaine microinjection, chronic thalamic stimulation may be an alternative for the long term control of tremor in these patients.
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PMID:Tremor reduction by microinjection of lidocaine during stereotactic surgery. 810

Parkinsonian tremor can be abolished by chronic high frequency thalamic stimulation of the ventral intermediate nucleus. We have studied six patients with unilateral Parkinson's disease. The patients had an electrode chronically implanted in the ventral intermediate nucleus of the thalamus. We measured changes in cerebral activity by positron emission tomography using an index of regional cerebral blood flow (rCBF). Each patient was scanned in three states: (i) tremor without stimulation (condition A); (ii) tremor with ineffective stimulation (condition B); (iii) tremor abolished by effective stimulation (condition C). The suppression of tremor (C compared with B) was specifically associated with a decrease of rCBF in the cerebellum, whereas the ineffective stimulation (B compared with A) induced a decrease of rCBF in homolateral cerebral cortex. The results give evidence for different contributions from cortex and cerebellum to the generation of parkinsonian tremor and suggest that tremor suppression is mainly associated with a decrease of synaptic activity in the cerebellum.
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PMID:Thalamic stimulation and suppression of parkinsonian tremor. Evidence of a cerebellar deactivation using positron emission tomography. 845 62

Actigraphy, the long-term assessment of wrist movements, is used in several research fields, among which are included sleep and circadian rhythms. Actigraphs record movements using accelerometers. The present paper addresses some basic problems and their solutions in the actigraphic assessment of movement, motor symptoms, circadian rest-activity rhythms, and nocturnal agitation in healthy elderly and elderly suffering from a neurodegenerative disease (i.e., Parkinson's disease or Alzheimer's disease) and summarizes the results of previous and ongoing research. First, we have investigated how to filter the accelerometer signal in order to minimize the contribution of accelerations induced by positional changes in the gravitational field--a strong source of artefacts. A bandpass filter from 0.5 to 11 Hz appropriately assesses movement induced accelerations while minimizing gravitational artefact. The application of a bandpass filter from 0.25 to 2 or 3 Hz, as is used in some of the commercially available actigraphs, results in artefacts and moreover biases the slower part of the movement spectrum. It is therefore far from optimal for research on aging, which is associated with a generalized motor slowing. Second, we have proposed an alternative to traditional methods of signal processing in actigraphy, in order to assess both the duration and intensity of movements, and in order to distinguish Parkinsonian tremor. Based on this algorithm, new types of actigraphs have been designed. Third, we have proposed sensitive variables in order to quantify rest-activity rhythm disturbances in healthy elderly subjects and Alzheimer patients, who often present with symptoms of nocturnal restlessness. Since, in these subjects, research protocols applying enforced phase shifts or time-free environments are unfeasible and not justifiable from an ethical point of view, the variables were specifically designed to assess the functionality of the circadian timing system from actigraphic recordings made in the natural environment of subjects. Examples of the application of actigraphy are given, including studies on symptom fluctuations and medication responses in Parkinson patients, and studies on circadian rhythm disturbances and possible remedies in elderly and Alzheimer patients.
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PMID:Actigraphic monitoring of movement and rest-activity rhythms in aging, Alzheimer's disease, and Parkinson's disease. 942 65

The thalamus is assumed to be involved in the generation of Parkinsonian tremor. Ten patients with tremor-dominant idiopathic Parkinson's disease (IPD) and strictly unilateral resting tremor were investigated by cerebral high-resolution 3-dimensional magnetic resonance imaging (MRI). MRI data were analyzed by an observer-independent morphometric technique, voxel-based morphometry (VBM). For VBM, MRI data were automatically normalized and segmented, then gray matter volumes were analyzed on a voxel-by-voxel basis in comparison to an age-matched control group using Statistical Parametric Mapping (SPM99). Highly significant structural changes, i.e. locally increased gray matter concentrations (P<0.001), were found in the nucleus ventralis intermedius (VIM) of the thalamus contralateral to the tremor side and were significantly covariant with tremor amplitudes. On the one hand, these changes were localized in close vicinity to a thalamic focal hypermetabolism as revealed by a previous positron emission tomography study in unilateral Parkinsonian tremor patients. On the other hand, the localization of the focal structural changes in VIM corresponds with the generally accepted target area of tremor surgery in IPD.
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PMID:Thalamic gray matter changes in unilateral Parkinsonian resting tremor: a voxel-based morphometric analysis of 3-dimensional magnetic resonance imaging. 1191 83

Voluntary finger-nose movements of the arm were analysed in six patients undergoing stereotaxic nucleus ventralis intermedius thalamotomy for relief of severe Parkinsonian tremor. In all cases thalamotomy acutely abolished tremor in the contralateral arm. In the early postoperative phase, ataxia of the arm contralateral to the operated side was also seen. Ataxia was transient, lasting between 7 and 21 days postoperatively. This observation suggests that a lesion of the Vim nucleus interrupts cerebellar input to the thalamus, and supports the concept that abnormal cerebellar activity is an important contributor to the generation of tremor in Parkinson's disease.
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PMID:Ataxic arm movements after thalamotomy for Parkinsonian tremor. 1253 64


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