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)

We studied the EMG potentials evoked in the bilateral first dorsal interosseus muscle by electromagnetic stimulation of the corticomotoneuronal descending system in 10 Parkinson's disease patients and in 10 age- and sex-matched normal controls. We selected patients who did not have tremor but had predominant rigidity with asymmetric body involvement. On the rigid side of the PD patients, the threshold to cortical stimulation was lower than on the contralateral side or than normal values. On average, patients had normal central conduction times, but their motor evoked potentials (MEPs) on the rigid side were larger than those of controls when the cortical stimulus was at rest or during slight tonic contraction of the target muscle. In the latter condition, a silent period shorter than that of controls followed MEPs, whereas the peripheral silent period following ulnar nerve stimulation at the wrist was prolonged. Alpha motor neuron excitability, tested by the F-wave method, was enhanced on the rigid side at rest. In rigidity, spinal motor nuclei may be more responsive than normal to descending inputs from motor cortex, or the entire corticomotoneuron system may prove hyperexcitable under given conditions.
Neurology 1991 Sep
PMID:Parkinson's disease rigidity: magnetic motor evoked potentials in a small hand muscle. 189 Oct 97

We studied motor initiation and execution using wrist extension movements to changing target locations in eight normal subjects and nine Parkinson's disease (PD) patients before and after medications. Late changes resulted in double trajectories, indicating commitment to the initial target acquisition program followed by a correcting movement. There was compensation for earlier changes, even after onset of agonist muscle activity, resulting in a single trajectory, implying that the original trajectory had not yet been specified. However, movements were slowed in PD patients implying an abnormality in the content of the target acquisition program but not in the timing of its specification. In PD patients, the timing of the second movement onset correlated best with the timing of target location change and did not depend on initial movement completion. Thus, PD patients were able to program the second movement while the first movement was under way.
Neurology 1991 Sep
PMID:Motor initiation versus execution in normal and Parkinson's disease subjects. 189 Nov 1

We examined reaction times, movement velocities, and the associated agonist and antagonist muscle behaviors in nine Parkinson's disease (PD) patients and eight normal subjects before and after medications, using a wrist extension task to changing locations of a visual target. Targets changing 500 msec before an auditory "go" signal act as a preparatory cue, while targets changing at the time of the go signal provide a combined auditory and visual stimulus. Late target changes allowed examination of (1) reaction times during an ongoing movement, and (2) movement in the presence and absence of visual targets. PD prolonged the time from the onset agonist electromyographic activity and reduction of antagonist activity to movement onset. Both were shortened by preparatory cues and combined visual and auditory go signals. PD slowed movement only in a subset of trials in which there was movement to a displayed target.
Neurology 1991 Sep
PMID:Reaction time and movement velocity abnormalities in Parkinson's disease under different task conditions. 189 Nov 2

The motor deficits associated with Parkinson's disease may be ameliorated by intrastriatal placement of dopamine-secreting cells in a polymer capsule. Water soluble polyelectrolytes were utilized for membrane encapsulation of dopamine-secreting PC12 cells. Membrane permeability studies revealed exclusion of radiolabeled 69,000 Da albumin, whereas 30,000 Da carbonic anhydrase was able to cross the membrane. No cytolytic activity was observed following incubation of the encapsulated PC12 cells with PC12 cell-directed antiserum and fresh complement. In vitro, dopamine release and the surface area of intact cells per microcapsule, reached a plateau at 4 weeks that was maintained for at least 12 weeks. Viable PC12 cells were observed in microcapsules implanted for 4 and 8 weeks in nonlesioned guinea pig striata. The behavioral effect of intrastriatal dopamine release from microencapsulated PC12 cells was evaluated in the 6-hydroxydopamine unilaterally lesioned rat model. From 1 to 4 weeks postimplantation a significant reduction in rotation behavior under apomorphine challenge was observed with PC12 cell-loaded microcapsules as compared to empty microcapsules. Tyrosine hydroxylase immunopositive PC12 cells were observed 4 weeks postimplantation in all animals exhibiting a reduction in turning behavior. Implantation of polymer-encapsulated cells may provide a means for long-term delivery of neurotransmitters and growth factors to the nervous system.
Exp Neurol 1991 Sep
PMID:Behavioral recovery following intrastriatal implantation of microencapsulated PC12 cells. 191 23

After local surgical exposure, we administrated 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) directly into the right common carotid artery of 5 rhesus monkeys. All the monkeys manifested akinesia, rigidity and postural tremor of the contralateral limbs, and spontaneous circling toward the MPTP treated side. These disturbances began to appear 3-4 days after injection, peaking at one month, and continued until the day of sacrifice. After treatment with madopar and apomorphine, marked improvements of the motor impairments appeared and a striking reversal of the direction of rotation away from the MPTP-treated side occurred in a dose-dependent manner. The ipsilateral neurotoxicity was confirmed biochemically by 99% reduction in the caudate-putamen dopamine levels and histologically by selective cell loss in the substantia nigra of the MPTP-treated side. It is concluded that this primate model of hemiparkinsonism is easy to reproduce and life is maintained with good health otherwise. So it may be more feasible for behavioral and pharmacological studies of Parkinson's disease.
Chin Med J (Engl) 1991 Sep
PMID:Hemiparkinsonism in monkeys following unilateral common carotid artery infusion of MPTP. A study of behavior, biochemistry and histology. 193 58

The cerebrospinal fluid (CSF) is a specific ultrafiltrate of plasma, which surrounds the brain and spinal cord. The study of its proteins and their alteration may yield useful information on several neurological diseases. By using various electrophoretic separation techniques, several CSF proteins have been identified derived from plasma or from brain. Different one-dimensional methods, such as agarose gel electrophoresis and isoelectric focusing, are of similar value in identifying the non-specific oligoclonal bands, which are mainly helpful in the diagnosis of multiple sclerosis and other inflammatory diseases. Isoelectric focusing has a greater resolution than other one-dimensional methods, and it yields additional data about disease-associated proteins occurring in Alzheimer's disease, Huntington's chorea and amyotrophic lateral sclerosis. Silver-stained two-dimensional gels provide more information about the complex protein composition of CSF, particularly about proteins produced in the brain, such as apolipoprotein E and neuron-specific enolase. For the detection of oligoclonal antibodies, the investigation of protein changes revealed by Parkinson's disease, schizophrenia and Creutzfeldt-Jakob disease, and the analysis of CSF immune complexes, two-dimensional electrophoresis has a greater sensitivity.
J Chromatogr 1991 Sep 13
PMID:Analysis of cerebrospinal fluid proteins by electrophoresis. 193 90

In later stages of the disease, patients with Parkinson's disease treated with levodopa may become severely disabled by pronounced and sudden motor fluctuations called "the on-off syndrome". In spite of optimal individual adjustment of doses and combinations, orally administered antiparkinson drugs are often not able to eliminate the off-conditions which may last from minutes to hours and sometimes are accompanied by dystonic pain. Apomorphine, a potent dopamine receptor agonist, administered subcutaneously as single injections or continuously by means of a pump, quickly passes on to striatal dopamine receptors. With suitable individually adjusted doses, a rapid, and in some cases, more stable anti-parkinson effect may be achieved. Peripheral side-effects can be avoided by concomitant treatment with domperidone. Nine levodopa treated patients with Parkinson's disease and severe on-off syndrome received apomorphine. Seven experienced considerable and long-term improvement of the disabling symptoms, and some patients reduction of levodopa and/or bromocriptine doses. Treatment with apomorphine should only be considered in patients whose on-conditions are not accompanied by pronounced dyskinesias and/or impairment of balance or to patients suffering from severe dystonic pain.
Ugeskr Laeger 1991 Sep 16
PMID:[Apomorphine in the treatment of Parkinson disease]. 194 72

The aim of this study was to examine contraction characteristics in striated muscles from Parkinson patients and to measure any changes in characteristics based on changes in medication. Fifteen patients, 9 men and 6 women, mean age 61.6 (range 43-70) with mild to moderate parkinsonism, (Hoehn and Yahr I-III) were investigated, and the results were compared with a group of 8 normal controls (mean age 59.6, range 50-70). Twelve of the patients (7 men and 5 women) were also tested after a 24-h period without medication. Using supramaximal electrical stimulation of the ulnary nerve at the wrist contraction, characteristics in the m. adductor pollicis muscle can be recorded. Stimulation results were printed on a fast paper writer. The following characteristics were recorded: 1) electromechanical delay of contraction EMDc; 2) contraction time to half tetanus CTT1/2; 3) electromechanical delay of relaxation EMDr; 4) relaxation rate RR for 10 ms RR-10; 5) the force produced in the tetanic contraction at stimulus frequencies 5, 10, 20, 50 Hz. The results showed that the in initiation of contraction (EMDc) was normal compared with controls. CTT1/2 was shorter (p less than 0.001) in the group of Parkinson patients compared with normals. EMDr was not changed when compared with normals, but RR-10 was increased, p less than 0.05. Force levels at the different stimulation rates were not significantly changed. After withdrawal of medication all parameters were unchanged. Muscle contraction characteristics in tetanic contraction were found to be abnormal indicating either a possible preactivation in the muscle contraction or a secondary change in the muscles of patients with Parkinson's disease.
Acta Neurol Scand 1991 Sep
PMID:Characteristics of tetanic muscle contraction in Parkinson patients. 195 Apr 69

Parkinson's disease has been associated with defects in oxidative phosphorylation (Oxphos). We analyzed mitochondria isolated from muscle biopsies of 6 patients with Parkinson's disease for deficiencies in Oxphos enzymes and for mutations in the mitochondrial DNA. Oxphos enzyme assays were compared to the 5 to 95% confidence intervals from 16 control subjects. Four patients had complex I defects, whereas 1 patient had a complex IV defect. A genetic basis for Parkinson's disease was suggested by the presence of affected relatives of 2 patients with Parkinson's disease. Known pathological mitochondrial DNA mutations (insertion-deletions or point mutations) were not found. We conclude that Parkinson's disease is a systemic disorder of Oxphos, probably of a complex genetic etiology. Premature cell death in the nigrostriatal dopamine pathway could be due to energetic impairment and accentuated free radical generation caused by an Oxphos defect.
Ann Neurol 1991 Sep
PMID:Mitochondrial oxidative phosphorylation defects in Parkinson's disease. 147 44

The substrate for olivopontocerebellar atrophy parkinsonism is obscure due to the lack of clinical and pathological reports and the absence of studies on dopamine receptors in this entity. We describe a patient with olivopontocerebellar atrophy whose clinical presentation was levodopa-responsive parkinsonism in whom pathological examination disclosed pronounced nigral cell loss with no striatal damage. Autoradiographic labeling with 3H-spiperone showed normal densities of D2 dopamine striatal receptors. These data show that indistinguishable nigral, presynaptic parkinsonism occurs in patients with idiopathic Parkinson's disease and in patients with olivopontocerebellar atrophy, and also how a favorable response to levodopa is neither synonymous with idiopathic Parkinson's disease, nor does it exclude multiple-system, atrophy-related parkinsonism.
Ann Neurol 1991 Sep
PMID:Presynaptic parkinsonism in olivopontocerebellar atrophy: clinical, pathological, and neurochemical evidence. 195 31


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