Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0233565 (bradykinesia)
 2,352 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Basal ganglia have been known as a motor center because their lesions cause motor disturbances in involuntary movements such as chorea, ballism or akinesia in parkinsonism. The different types of involuntary movements are closely related to the underlying muscle tone. Mechanisms of bradykinesia or akinesia have been elaborated in physiological studies on Parkinson's disease and the significance of sensorimotor processing or attention arousal has been disclosed as a relevant factor of bradykinesia. Analysis of short-stepped gait, frozen gait or apraxia of gait, has claimed the frontal lobe and the striatum to be a locomotion center especially in humans (bipedal locomotion). Cognitive function of the basal ganglia has attracted attention particularly in the disorder of Parkinson's disease. Subcortical dementia, difficulty in formation or changes of concepts are encountered in advanced stages of Parkinson's disease. Whether cognitive functions in the frontostriatal system are primarily related to the motor function of the brain is an issue for future study.
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PMID:Historical review of research on functions of basal ganglia. 879 Oct 14

Posteroventral pallidotomy (PVP) was carried out in 86 patients with Parkinson's disease, who presented marked bradykinesia, freezing of gait and postural defect associated with rigidity and tremor in 82 patients (bradykinesia type), and similar gait and postural problems with minimum signs of rigidity and tremor in 4 (pure akinesia type). The stereotactic coordinates of Leksell's device were calculated from MRI and conventional ventriculography. The final target was defined by microelectrode techniques in the basal ganglia. The microrecording study revealed a very high background activity in the internal pallidum in patients of the bradykinetic type, however, a much lower pallidal activity in patients of the pure akinesia type. Fifty-eight patients underwent unilateral PVP, and 28 underwent bilateral surgery. Following PVP, rigidity tremor and poor reciprocal movements were significantly improved especially in the contralateral extremities. The most dramatic findings were the reversal of akinetic symptoms and wearing-off phenomena. The patients were followed up for 3-30 months (mean = 8) after surgery. Of the 82 bradykinesia type patients, good result were obtained in 48 (58%), fair results in 26 (32%), and minor improvement or no change in 8 (10%). In all the 4 patients of the pure akinesia type, recurrence of the akinetic symptoms occurred after a temporal improvement lasting a few days to 3 month after surgery. There was worst dysarthria in 3 patients, hemiparesis in 1 and partial motor aphasia in 1. The visual field problem was not complicated in any patients. These findings suggest that akinetic symptoms in PD are implicated in overactive pallidal outputs with putative GABAergic modulator by excessively inhibiting pedunculopontine nucleus activity (midbrain locomotor and posture regions) as well as thalamic activity. Partial interruption of the pallidal efferents eliminates the akinetic symptoms by disinhibitory effects on the target structures. The pathology of PD of the pure akinesia type is supposedly in the brainstem and should be excluded from indication of pallidotomy.
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PMID:Surgical control of akinesia in Parkinson's disease. 879 Oct 23

The effects of posterior internal pallidal ablation (GPi pallidotomy) on parkinsonian signs and symptoms were studied in 15 patients with medically intractable Parkinson's disease (PD). The sensorimotor territory of the internal portion of the globus pallidus and the adjacent optic tract and internal capsule were identified with microelectrode recording and stimulation. Radiofrequency lesions were then created in the identified sensorimotor territory. Pallidotomy significantly improved all cardinal parkinsonian motor signs (tremor, rigidity, akinesia/bradykinesia, and gait dysfunction) and reduced drug-induced motor fluctuations and dyskinesias. The improvements occurred predominately contralateral to the lesion, but were also present ipsilaterally. Early postoperative (3-month), mean total United Parkinson's Disease Rating Scale scores improved by 30.1% from preoperative values. Mean combined "on/off" Schwab and England Scale scores, a measure of functional independence, increased from 48.8% to 73.0% postoperatively. The mean total United Parkinson's Disease Rating Scale and Schwab and England scores did not show a statistically significant decline over the 1-year postoperative period. Surgery resulted in little morbidity, including a lack of significant deficits on neuropsychological and psychiatric testing. Physical and social functioning and vitality measures on the Medical Outcome Scale also showed significant improvement over the postoperative period. The findings of this pilot study demonstrate that ablation of the sensorimotor portion of the internal pallidum is a highly effective treatment for advanced PD, with benefits sustained at 1 year.
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PMID:Treatment of advanced Parkinson's disease by posterior GPi pallidotomy: 1-year results of a pilot study. 922 97

Experimental studies in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys have shown that akinesia and rigidity are linked to a hyperactivity of glutamatergic subthalamic nucleus neurons and that the lesion of this nucleus can ameliorate parkinsonian motor signs. In our study, high-frequency stimulation applied at the subthalamic level was performed on two Macaca mulatta monkeys rendered hemiparkinsonian by unilateral infusion of MPTP. Its effects on rigidity and bradykinesia have been quantified. The results exhibit an important alleviation of both symptoms during the application of subthalamic stimulation comparable to that obtained during L-Dopa treatment, but without the appearance of abnormal movements such hemiballism or dyskinesia. Our data show that subthalamic stimulation has a beneficial effect on experimental parkinsonian rigidity and bradykinesia and suggests a new therapy approach for the treatment of Parkinson's disease by using subthalamic high-frequency stimulation instead of L-Dopa treatment.
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PMID:Alleviation of experimental hemiparkinsonism by high-frequency stimulation of the subthalamic nucleus in primates: a comparison with L-Dopa treatment. 891 87

Animal models are an important aid in experimental medical science because they enable one to study the pathogenetic mechanisms and the therapeutic principles of treating the functional disturbances (symptoms) of human diseases. Once the causative mechanism is understood, animal models are also helpful in the development of therapeutic approaches exploiting this understanding. On the basis of experimental and clinical findings. Parkinson's disease (PD) became the first neurological disease to be treated palliatively by neurotransmitter replacement therapy. The pathological hallmark of PD is a specific degeneration of nigral and other pigmented brainstem nuclei, with a characteristic inclusion, the Lewy body, in remaining nerve cells. There is now a lot of evidence that degeneration of the dopaminergic nigral neurones and the resulting striatal dopamine-deficiency syndrome are responsible for its classic motor symptoms akinesia and bradykinesia. PD is one of many human diseases which do not appear to have spontaneously arisen in animals. The characteristic features of the disease can however be more or less faithfully imitated in animals through the administration of various neurotoxic agents and drugs disturbing the dopaminergic neurotransmission. The cause of chronic nigral cell death in PD and the underlying mechanisms remain elusive. The partial elucidation of the processes underlie the selective action of neurotoxic substances such as 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), has however revealed possible molecular mechanisms that give rise to neuronal death. Accordingly, hypotheses concerning the mechanisms of these neurotoxines have been related to the pathogenesis of nigral cell death in PD. The present contribution starts out by describing some of the clinical, pathological and neurochemical phenomena of PD. The currently most important animal models (e.g. the reserpine model, neuroleptic-induced catalepsy, tremor models, experimentally-induced degeneration of nigrostriatal dopaminergic neurons with 6-OHDA, methamphetamine, MPTP, MPP+, tetrahydroisoquinolines, beta-carbolines, and iron) critically reviewed next, and are compared with the characteristic features of the disease in man.
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PMID:Animal models of Parkinson's disease: an empirical comparison with the phenomenology of the disease in man. 901 91

Studies of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism in monkeys suggest that excessive inhibitory outflow from the internal segment of the globus pallidus (GPi) suppresses the motor thalamus, which reduces activation of the cerebral cortex motor system, resulting in the slowness and poverty of movement of Parkinson's disease (PD). This hypothesis is supported by reports of high rates of spontaneous neuronal discharges and hypermetabolism in GPi (ref. 4-7) and impaired activation of the supplementary motor area (SMA) and dorsolateral prefrontal regions in PD patients. Furthermore, lesion or chronic high-frequency electrical (likely inactivating) stimulation of GPi (ref. 10-14) is associated with marked improvements in akinesia and rigidity, and the impaired activation of SMA is reversed when the akinesia is treated with dopamine agonists. To test whether improvement in motor function with pallidal surgery can be attributed to increased activity in premotor cortical regions, we assessed the changes in regional cerebral blood flow (rCBF) and parkinsonian symptoms during disruption of GPi activity with high-frequency stimulation delivered through implanted brain electrodes. Positron emission tomography (PET) revealed an increase in rCBF in ipsilateral premotor cortical areas during GPi stimulation, which improved rigidity and bradykinesia. These results suggest that disrupting the excessive inhibitory output of the basal ganglia reverses parkinsonism, via a thalamic relay, by activation of brain areas involved in the initiation of movement.
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PMID:Globus pallidus stimulation activates the cortical motor system during alleviation of parkinsonian symptoms. 917 79

The effectiveness of ventroposterolateral pallidotomy in the treatment of akinesia and rigidity is not a new discovery and agrees with recent investigations into the pathogenesis of Parkinson's disease, which highlight the role played by the unbridled activity of the subthalamic nucleus (STN) and the consequent overactivity of the globus pallidus internalis (GPi). Because high-frequency stimulation can reversibly incapacitate a nerve structure, we applied stimulation to the same target. Seven patients suffering from severe Parkinson's disease (Stages III-V on the Hoehn and Yahr scale) and, particularly, bradykinesia, rigidity, and levodopa-induced dyskinesias underwent unilateral electrode implantation in the posteroventral GPi. Follow-up evaluation using the regular Unified Parkinson's Disease Rating Scale has been conducted for 1 year in all seven patients, 2 years in five of them, and 3 years in one. In all cases high-frequency stimulation has alleviated akinesia and rigidity and has generally improved gait and speech disturbances. In some cases tremor was attenuated. In a similar manner, the authors observed a marked diminution in levodopa-induced dyskinesias. This could be an excellent primary therapy for younger patients exhibiting severe bradykinesia, rigidity, and levodopa-induced dyskinesias, which would allow therapists to keep ventroposterolateral pallidotomy in reserve as a second weapon.
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PMID:High-frequency stimulation of the globus pallidus internalis in Parkinson's disease: a study of seven cases. 932 38

Atypical neuroleptics present a unique opportunity to examine confounding by neuroleptic-induced extrapyramidal symptoms (EPS) in the assessment of negative signs of schizophrenia. EPS, such as facial bradykinesia and akinesia, involve some of the same response systems and phenomena as emotional display channels. EPS are attributed to the blockade of dopamine receptors in the striatum by traditional neuroleptics. Newer atypical neuroleptics target primarily mesolimbic and mesocortical areas, and receptors for other transmitters such as serotonin. Olanzapine has been reported as less likely to cause EPS and may improve some negative signs. We investigated the relationship between measures of EPS and negative symptoms in patients with schizophrenia treated with haloperidol or olanzapine. Patients were rated with the Positive and Negative Syndrome Scale (PANSS) and the Simpson-Angus Scale EPS scale. Results show that the two agents have comparable efficacy but different safety outcomes. A positive correlation between EPS and PANSS negative score was detected in the haloperidol group only. Stepwise multiple regression analysis shows that a big proportion of variability in PANSS negative symptoms is predicted by EPS in the haloperidol group, but not in the olanzapine group, even though EPS increased in patients treated with haloperidol but not in olanzapine patients.
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PMID:The relationship between negative symptoms of schizophrenia and extrapyramidal side effects with haloperidol and olanzapine. 956 1

Progressive supranuclear paly (PSP) was firstly reported by Steel in 1964. This condition was separated from Parkinsonism by both clinical symptoms and neuropathological findings. Recently, in an attempt to improve diagnostic accuracy to give appropriate informed concepts and to select correct cases for drug studies or other research purpose, diagnostic criteria for PSP have been developed. PSP begins in the presenile period and duration of illness is 5.9 years (1.2-10.3 years; Maher and Lees, 1986). Cardinal clinical symptoms of PSP are supranuclear gaze palsy, neck dystonia, parkinsonism, pseudobulbar palsy, gait imbalance with frequent falls and subcortical dementia. Supranuclear gaze palsy and bradykinesia are essential for diagnosis. MR-imaging of PSP shows dilatation of the third ventricle. Other laboratory examinations show no specific findings. Neuropathologically, marked dilation of the third ventricle and volume loss of periaqueductal area of the midbrain are noted in macroscopic view. Microscopical examination reveals neuronal loss and gliosis in the tegmentum, the tectum, periaqueductal gray, the dentate-rubro-pallido-luysial area, and the inferior olivary nucleus. Neuropathological hallmarks of PSP are neuronal loss, presence of the globose typed neurofibrillary degeneration, and glial tangles (so called tuft shaped astrocyte and coiled body). Atypical cases of PSP are reported. Such cases are reported as pure akinesia, PSP without ophthalmoplegia, dementia predominant PSP, pathologically diagnosed pallido-nigro-luysial atrophy (PNLA), pathologically diagnosed corticobasal degeneration which showed no laterality, and so on. Reported cases as pure akinesia was diagnosed as PSP or PNLA by neuropathological findings. Improvement of diagnostic accuracy in PSP is expected to ithrapeutic trials, to investigate the etiology, and to separate the other clinical entity from PSP.
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PMID:[Progressive supranuclear palsy]. 957 67

We reported a 73-year-old man with pure akinesia syndrome who showed severe acquired stuttering and paradoxical kinesia on speech. He was evaluated in another hospital for bradykinesia and frozen gait at age of 67 when his cranial MRI disclosed ischemic changes in bilateral basal ganglia and periventricular deep white matter. The treatment with L-dopa and L-threo DOPS was not effective. His symptoms were slowly progressive and got worse gradually. At age of 72, he began to have difficulty in speech due to severe acquired stuttering, and one year later, he visited our hospital. The diagnosis of pure akinesia syndrome was made because of akinesia, micrographia, marked frozen gait with paradoxical kinesia and disturbance of postural reflex without tremor and rigidity. His speech showed severe acquired stuttering with marked blocking and repetition of initial phonemes at the beginning of speech. But intelligible speech recurred with pointing the characters by his finger or with writing an initial letter of word, although his speech was small and monotonous. Surface EMG findings of muscles participating speech in acquired stuttering showed the similar tonic discharge to those of muscles of lower extremity in frozen gait. These results implied that freezing phenomenon and festination of muscles participating speech in our patient may result in acquired stuttering.
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PMID:[A management for severe acquired stuttering in a case of pure akinesia syndrome]. 959 12


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