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)

Pathophysiological mechanisms of major symptoms of Parkinson's disease are discussed from experiences of stereotaxic surgery. Tremor completely disappears by a lesion in the ventral intermediate nucleus(Vim) which receives proprioceptive sense from the periphery. Rigidity is alleviated by a lesion in the globus pallidus(GP) and the ventral lateral nucleus(VL) equally. Since GP projects to the prefrontal motor cortex via VL, surgery to either of those structures causes the same result. Akinesia is classified into three types: secondary akinesia, primary akinesia, and akinesia due to psychomotor dysfunction. Gradual spread of neuronal degeneration within the substantia nigra pars compacta may explain the progression of akinesia. Psychological or psychiatric disorder becomes major symptom in the late stage. Posteroventral pallidotomy may change emotional state in some cases by influencing the limbic motor circuit.
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PMID:[Clinical pathophysiology of parkinsonian symptoms: from experiences of stereotaxic surgery]. 1106 35

Pallidotomy has recently regained acceptance as an effective treatment for Parkinson's disease. From our 50 cases of unilateral pallidotomy and 10 cases of staged bilateral pallidotomy, details and indications of the procedure is described. The unilateral pallidotomy is quite effective for L-dopa induced dyskinesia, which usually completely disappears soon after the operation. The effect is long-lasting. When on-off phenomenon exists, unilateral pallidotomy improves off-stage rigidity or akinesia. Symptoms during on-stage are not changed. Indications of pallidotomy is that(1) L-dopa induced dyskinesia, and(2) on-off phenomenon. Bilateral pallidotomy, even by staged one, causes severe drooling, or speech disturbance(the volume of the voice decreases and the articulation worsens), and is not recommended. Vim thalamotomy is, on the other hand, the established treatment for tremor of Parkinson's disease or of essential tremor. The effect is long-lasting. Rigidity or akinesia is not expected to be improved so much.
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PMID:[Details and indications of pallidotomy and thalamotomy for Parkinson's disease]. 1106 49

Tremor is the most common initial symptom and one of the cardinal features of Parkinson's disease. Mild tremor causes only minimal disability, but severe tremor causes more significant disability and distress for the patient than rigidity and/or bradykinesia. Anticholinergic agents, levodopa/DCI and dopamine agonists are most common and beneficial in parkinsonian tremor, but efficacies of these medications are variable among patients. Rigidity and bradykinesia are more responsive to levodopa/DCI therapy than tremor. Clozapine is an atypical neuroleptic agent, not on the market in Japan, and has been reported to decrease or ameliorate parkinsonian tremor through the studies of open label and double blind crossover as a new drug for parkinsonian tremor.
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PMID:[Pharmacological treatment of parkinsonian tremor]. 1106 52

GAIT ARRESTS: They affect the evolution of the disease. This freezing phenomenon which induces falls sometimes constitutes an initial sign. Like the gait initiation failure, freezing can be controlled by sensory stimulation, notably visual inputs, but also by more sustained attention. FALLS ARE MAINLY CONNECTED WITH BOTH POSTURAL INSTABILITY AND RIGIDITY: They are poorly influenced by dopaminergic therapies. The progressive decrease of step width represents a main factor in their occurrence. PRECOCITY OF GAIT DISORDERS IS UNUSUAL IN PARKINSON'S DISEASE: Other parkinsonian syndromes such as progressive supranuclear palsy, multiple system atrophy and vascular parkinsonian syndrome must then be evoked. Their association with a cognitive impairment and abnormal sphincter behaviour infers a diagnosis of normal pressure hydrocephalus. GAIT IMPROVES WITH L-DOPA THERAPY: Speed, step length and duration of the swing phase are increased without change of cadence. Progressive loss of L-dopa efficiency on gait and postural stability contrasts with the persistent effect on tremor, rigidity and bradykinesia; a functional abnormality of nondopaminergic systems can explain these symptoms. In the following stages, gait troubles increased by motor fluctuations and abnormal involuntary movements are less controlled by L-dopa therapy. PHYSICAL THERAPY PLAYS A MAJOR ROLE IN THERAPEUTIC MANAGEMENT: An individual or collective rehabilitation project must be established according to the stage of evolution; the exercises aim to protect postural control and coordination. Visual or sound rhythmic inputs can be employed in the case of gait initiation failure. THE EFFECTS OF FUNCTIONAL NEUROSURGERY ARE IN THE COURSE OF EVALUATION: Thermolesion and chronic electrical stimulation of deep brain structures have opposite effects on gait troubles. Bilateral thalamotomy or pallidotomy are sometimes a source of disequilibrium. Chronic thalamic stimulation does not induce either benefits or adverse effects. On the other hand, stimulation of the internal pallidum improves gait kinematic parameters; improved postural adjustments have also been reported. The effect of subthalamic nucleus stimulation is comparable to that of L-dopa, however the long-term effect remains to be evaluated.
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PMID:[Gait disorders in Parkinson disease. Gait freezing and falls: therapeutic management]. 1128 86

The aim of the present study was to find out whether blockade of adenosine A(2A) receptors by a selective antagonist, SCH 58261, influenced parkinsonian-like muscle rigidity. Muscle tone was examined using a combined mechano- and electromyographic method which simultaneously measured muscle resistance (MMG) of a rat hindfoot to passive extension and flexion in the ankle joint and electromyographic activity (EMG) of the antagonistic muscles of that joint: gastrocnemius and tibialis anterior. Muscle rigidity produced by reserpine (5 mg/kg + alpha-methyl-p-tyrosine, 250 mg/kg) was antagonized by SCH 58261 (0.1-5 mg/kg). SCH 58261 (5 mg/kg) also reduced reserpine-enhanced tonic and reflex EMG activities in both the gastrocnemius and the tibialis muscles. Moreover, SCH 58261 in doses of 1 and 5 mg/kg abolished muscle resistance induced by haloperidol (0.5 mg/kg). However, only the highest dose of SCH 58261 (5 mg/kg) decreased tonic EMG activity enhanced by haloperidol. Administration of L-DOPA (75 and 100 mg/kg) dose-dependently decreased the muscle resistance as well as tonic EMG activity evoked by haloperidol. Combined administration of SCH 58261 (0.1 mg/kg) and L-DOPA (50 mg/kg) in doses which did not affect the haloperidol-induced muscle rigidity produced a pronounced synergistic effect. The ability of SCH 58261 to diminish the parkinsonian-like muscle rigidity and to potentiate the effect of L-DOPA in this model seems to indicate a therapeutic value of this compound in the treatment of Parkinson's disease.
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PMID:SCH 58261, an A(2A) adenosine receptor antagonist, counteracts parkinsonian-like muscle rigidity in rats. 1140 Jan 82

We report a 56-year-old woman with progressive gait disturbance. Her mother had Parkinson's disease with onset at age 70. She died at age 74 and the post-mortem examination confirmed the diagnosis of Lewy body positive Parkinson's disease. The patient was well until the age of 50(1995) when she noted an onset of resting tremor and difficulty of gait. She also developed delusional ideation and was admitted to a psychiatric service of another hospital, where a major tranquilizer was given. The delusion disappeared but she developed marked rigidity. The major tranquilizer was discontinued and an anticholinergic and amantadine HCl were given. She showed marked improvement to Hoehn and Yahr stage II and was discharged. In 1995, when she was 52 years of the age, she developed delusion again and a major tranquilizer was given. She developed marked parkinsonism again and became Hoehn and Yahr stage V. The major tranquilizer was discontinued and she was treated with levodopa/carbidopa, trihexyphenidyl, bromocriptine, and dops. She improved remarkably to stage II. She was admitted to our service on October 8, 1996 for drug adjustment. She was alert and not demented. She was anxious but delusion or hallucination was noted. Higher cerebral functions were intact. Cranial nerve functions were also intact except for masked face and small voice. Her posture was stooped and steps were small. She showed retropulsion and moderate bradykinesia. Resting tremor was noted in her left hand. Rigidity was noted in both legs. No cerebellar ataxia or weakness was noted. Deep tendon reflexes were within normal range and sensation was intact. Her cranial MRI revealed some atrophic changes in the putamen, in which a T 2-high signal linear lesion was seen along the lateral border of the putamen bilaterally. In addition, posterior part of the putamen showed T 2-low signal intensity change. She was treated with 1.6 mg of talipexole, 6 mg of trihexyphenidyl, and 100 mg of L-dops. She was in stage III of Hoehn and Yahr. She developed neurogenic bladder with a large amount of residual urine for which she required catheterization. She was transferred to another hospital. Despite drug adjustment, she lost response to levodopa and her parkinsonism deteriorated gradually. She also developed syncope orthostatic hypotension. In April of 1998, she developed intracerebral hemorrhage and was admitted again on April 19, 1998. She was unable to stand and showed marked akinesia and rigidity. She was in stage V of Hoehn and Yahr. Her cranial CT scan revealed bilateral high-density lesions in the posterior parietal lobes. She developed dysphagia for which she required gastrostomy. She was transferred to another hospital but her clinical condition deteriorated further. On December 22, 1999, she developed fever and dyspnea and was admitted to our service again. She developed cardial arrest at the emergency room from hypoxia. She was resuscitated; however, she was comatose with loss of brain stem reflexes. Later on she developed generalized myoclonus. She developed cardiac arrest and pronounced dead on December 28, 1999. The patient was discussed in a neurological CPC. The chief discussant arrived at the conclusion that the patient had striatonigral degeneration because of poor response to levodopa in the later course, autonomic failures, and MRI changes. Some other participants thought that the patient had a form of familial Parkinson's disease. Opinions were divided into these two possibilities. Post-mortem examination revealed that the substantia nigra showed intense neuronal loss and gliosis, however, no Lewy bodies were seen. In addition, intracytoplasmic inclusions were seen in oligodendrocytes. The putamen was markedly atrophic in its posterior part with marked gliosis and neuronal loss. The ventromedial part of the pontine nucleus also showed neuronal loss and intracytoplasmic glial inclusions. Pathologic diagnosis was multiple system atrophy. In the parietal lobe, an arteriovenous malformation with bleeding was noted. This is very unique case. Although her mother had Lewy body-positive Parkinson's disease, the patient had Lewy body-negative multiple system atrophy with a-synuclein-positive glial inclusions. Whether this is just a coincidental occurrence or the presence of a genetic load for Parkinson's disease might triggered her multiple system atrophy is an interesting question to be answered in future.
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PMID:[A-56-year-old woman with parkinsonism, whose mother had Parkinson's disease]. 1142 77

Parkinson's disease is one of the most frequent neurodegenerative brain diseases. Its time course is slow and is characterized by progressive loss of dopaminergic and other brainstem neurons resulting in malfunctioning of the cerebral neuronal systems responsible for motor functions. The clinical signs are slowness of movement, muscle rigidity and rest-tremor amongst other features. The cause of the disease is unknown, but recently involvement of genetic factors is being researched. Positron emission tomography (PET) allows in vivo determination of striatal dopaminergic activity. This has increased our insight in the pathophysiology of the disease and permits direct study of disease progression at a biochemical level and equally to monitor whether potential neuroprotective interventions are indeed effective. Thus far no drug has emerged but promising substances are currently being studied.
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PMID:Parkinson's disease: clinical signs and symptoms, neural mechanisms, positron emission tomography, and therapeutic interventions. 1153 Aug 92

The authors of this paper view Parkinson's disease (PD) as a clinically defined progressive syndrome of resting limb tremor, bradykinesia, muscle rigidity, and a shuffling unsteady gait that responds well to dopaminergic medications. Parkinson's disease is a not a single entity, but rather a syndrome with diverse causes, with both genetic and environmental risk factors. The clinician's concern is to rule out other entities, especially those having another specific treatment, and to give PD patients the best short- and long-term benefit, with the least possible unwanted side effects.
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PMID:Long-term Medical Treatment for Parkinson's Disease. 1158 26

An 86-year old man presented with a 7-year history of gait disturbance. He was admitted to our hospital on April 2000 because he was experiencing difficulty eating due to progression of dropped head syndrome. Upon standing and sitting, remarkable dropped head and kyphosis were observed. When lying, the patient was able to stretch his neck, and he could stand and walk with the aid of a walker. Rigidity and resting tremor were present predominantly in the lower limbs. Parkinson's disease was diagnosed therefore L-dopa and Cabergoline were administered. Parkinsonism and dropped head syndrome improved in response to treatment. Cases involving dropped head syndrome due to Parkinson's disease are reportedly improved by L-dopa, but exasperated by dopamine agonists. The mechanism of dropped head is thought to be an imbalance in the tonus of the anterior and posterior neck muscles. Dropped head in the present case may have been a complication of Parkinson's disease since it improved in response to L-dopa.
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PMID:[A case of elderly onset Parkinson's disease complicated by dropped head syndrome]. 1160 21

The motor and neuropsychological abnormalities in eight Greek patients with Parkinson's disease (PD) carrying the alpha-synuclein gene mutation (G209A) were studied. These patients (five men, three women) belonged to six different families. Their symptoms started between 32-50 years of age (mean +/- SD, 39.7 +/- 7.6 years) and they had a mean disease duration of 5.4 +/- 2.1 years (range, 2-9 years) at the time of examination. Rigidity and bradykinesia predominated both at disease onset as well as in the later stages and rest tremor was relatively uncommon. Neuropsychological assessment showed that one patient was mildly demented while another had impairment in memory, visuoconstructive abilities, and executive function. Depression was present in only one patient. Our findings indicate that genetic forms of parkinsonism share common motor and cognitive characteristics with sporadic PD but raise the possibility that greater cognitive impairment and the relative rarity of tremor may be distinctive features worthy of further investigation.
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PMID:Clinical features of parkinsonian patients with the alpha-synuclein (G209A) mutation. 1221 Aug 94


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