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)

Levodopa (L-dopa) and subthalamic nucleus (STN) stimulation treatments have been associated with both improvement and exacerbation of dysarthria in Parkinson's disease (PD). We report four cases illustrating variant responses of dysarthria to dopaminergic and STN stimulation therapies. Patients' motor disability and dysarthria were perceptually rated by the Unified Parkinson's Disease Rating Scale (UPDRS) in four conditions according to medication and STN stimulation. Dedicated software packages allowed acquisition and analysis of acoustic recordings. Case 1, who had a severe off period aphonia, experienced improvement of speech induced by both levodopa and STN stimulation. In Case 2, both treatments worsened speech due to the appearance of dyskinesias. Case 3 had a dysarthria exacerbation induced by STN stimulation with parameters above optimal levels, interpreted as current diffusion from the STN to corticobulbar fibers. In Case 4, dysarthria exacerbation occurred with stimulation at an electrode contact located caudally to the target, also arguing for current diffusion as a potential mechanism of speech worsening. The presented cases demonstrated variant effects in relation to L-dopa and STN stimulation on speech. It seems that motor speech subcomponents can be improved like other limb motor aspect, but that complex coordination of all speech anatomical substrates is not responsive to STN stimulation. These hypotheses may be helpful for better understanding and management of STN stimulation effects on motor speech and skeleton-motor subsystems.
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PMID:Changes induced by levodopa and subthalamic nucleus stimulation on parkinsonian speech. 1603 17

We characterize the clinical features of Parkinson's syndrome on Guadeloupe and describe possible environmental causes. Consecutive patients who were referred to the University Hospital at Pointe a Pitre with parkinsonism from September 1996 to May 2002 were included. All cases were examined in a standardized manner by a neurologist with a special interest in movement disorders and independently by 3 external movement disorders specialists, using standard operational clinical diagnostic criteria. The subjects were 265 patients with Parkinson's syndrome living on Guadeloupe, four fifths of whom had been referred by primary care physicians and one fifth by neurologists. The levodopa response was assessed after a minimum period of 1 month of continuous treatment. All patients had brain computed tomography or brain magnetic resonance imaging scans and detailed neuropsychological examinations. Of 265 patients, only 66 were classified as Parkinson's disease, whereas 58 fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) and Society for Progressive Supranuclear Palsy (SPSP) criteria for progressive supranuclear palsy, 100 had unclassifiable parkinsonism, characterized by dopa-unresponsiveness, marked axial rigidity, relative symmetry of parkinsonian features, early dysarthria, and frontolimbic cognitive impairment. Within this group, early postural instability, dysarthria, a frontal behavior disorder, cortical or subcortical atrophy, pyramidal signs, axial rigidity, and family history of neurodegenerative disorders were associated with poorer prognosis. A very large number of unclassifiable cases of atypical parkinsonism that do not fulfill operational criteria for Parkinson's disease or other defined motor neurodegenerations has been observed on Guadeloupe. Most patients closely resemble descriptions of bodig from Guam. In both geographic isolates, an environmental cause has been discussed. Annonaceae fruits and herbal teas are consumed on both islands. These plants contain several neurotoxins, particularly acetogenins, which induce dopaminergic neuron loss in animals. Neuronal death involves cholinergic and dopaminergic cells of the substantia nigra and GABAergic neurons of the striatum, associated with microglial proliferation. The development of atypical parkinsonism in Guadeloupe and probably elsewhere, could result from synergistic toxicity, but acetogenins are probably the most potent neurotoxin, acting as mitochondrial complex I inhibitor.
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PMID:Atypical unclassifiable parkinsonism on Guadeloupe: an environmental toxic hypothesis. 1609

It is widely accepted that the cerebellar and basal ganglia control circuits contribute to the programming of movement. Converging evidence from neuroimaging, limb control, and neuropsychological studies suggests that (1) people with cerebellar disease have reduced ability to program movement sequences in advance of movement onset and (2) people with Parkinson's disease are unable to maintain a programmed response or to rapidly switch between responses. Despite a substantial supporting literature, no studies have addressed these potential areas of speech programming disruption for speakers with ataxic and hypokinetic dysarthria. Control participants and adults with dysarthria completed speech reaction time protocols designed to capture these aspects of utterance preparation. Results provided initial support for processing deficits in speakers with ataxic and hypokinetic dysarthria that are separable from motor execution impairments.
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PMID:Speech motor programming in hypokinetic and ataxic dysarthria. 1609 82

It has been hypothesized that lax vowels may be relatively unaffected by dysarthria, owing to the reduced vocal tract shapes required for these phonetic events (G. S. Turner, K. Tjaden, & G. Weismer, 1995). It also has been suggested that lax vowels may be especially susceptible to speech mode effects (M. A. Picheny, N. I. Durlach, & L. D. Braida, 1986). Studies evaluating these suggestions are lacking, however. The present study was an initial investigation of the vowel space area formed by the lax vowels /Iota/, /epsilon/, and /upsilon/, occurring in a passage read in habitual, fast, and slow conditions by speakers with amyotrophic lateral sclerosis (ALS), speakers with Parkinson's disease (PD), and healthy controls. Vowel space areas for speakers with ALS but not speakers with PD differed from those for the appropriate control group. Thus, only the results for the PD group support the hypothesis that lax vowel space areas for speakers with dysarthria should be similar to those for neurologically normal talkers. Compared with the habitual condition, rate reduction was associated with an expanded vowel space area for all of the healthy talkers but for only about half of the speakers with dysarthria. In addition, about half of the speakers in each group demonstrated a reduced vowel space area for the fast condition relative to the habitual condition, although the statistical analyses indicated no difference in vowel space areas for the fast and habitual conditions. The current study therefore provides only limited support for the idea that lax vowels are highly susceptible to speech mode effects, at least when the speech modes under consideration include faster-than-normal and slower-than normal rates. Clinical implications are discussed.
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PMID:Characteristics of the lax vowel space in dysarthria. 1619 72

Previous investigations employing electropalatography (EPG) have identified articulatory timing deficits in individuals with acquired dysarthria. However, this technology is yet to be applied to the articulatory timing disturbance present in Parkinson's disease (PD). As a result, the current investigation aimed to use EPG to comprehensively examine the temporal aspects of articulation in a group of nine individuals with PD at sentence, word and segment level. This investigation followed on from a prior study (McAuliffe, Ward and Murdoch) and similarly, aimed to compare the results of the participants with PD to a group of aged (n = 7) and young controls (n = 8) to determine if ageing contributed to any articulatory timing deficits observed. Participants were required to read aloud the phrase "I saw a _ today" with the EPG palate in-situ. Target words included the consonants /l/, /s/ and /t/ in initial position in both the /i/ and /a/ vowel environments. Perceptual investigation of speech rate was conducted in addition to objective measurement of sentence, word and segment duration. Segment durations included the total segment length and duration of the approach, closure/constriction and release phases of EPG consonant production. Results of the present study revealed impaired speech rate, perceptually, in the group with PD. However, this was not confirmed objectively. Electropalatographic investigation of segment durations indicated that, in general, the group with PD demonstrated segment durations consistent with the control groups. Only one significant difference was noted, with the group with PD exhibiting significantly increased duration of the release phase for /la/ when compared to both the control groups. It is, therefore, possible that EPG failed to detect lingual movement impairment as it does not measure the complete tongue movement towards and away from the hard palate. Furthermore, the contribution of individual variation to the present findings should not be overlooked.
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PMID:Speech production in Parkinson's disease: II. Acoustic and electropalatographic investigation of sentence, word and segment durations. 1639 96

The objective of this study was to determine the influence of stereotactic ablative surgical interventions on the time required for the performance of manual tasks (i.e. performance time) in patients with Parkinson's disease (PD). We studied 28 patients after pallidotomy and pallido-thalamotomy who were evaluated at four time: before the operation, and 2 days, 3 and 6 months postoperatively. The speed of performance of handwriting and drawing were assessed by means of a chronometer using certain parts of an international standard scale (modified by Fahn). The patients were also assessed according to the Unified Parkinson's Disease Rating Scale (UPDRS) part III. The patients were divided into two groups. Those in group A had relief of all main Parkinsonian symptoms after pallidotomy including tremor. The patients in group B had no relief of tremor straight after pallidotomy. For them the pallidotomy was completed with thalamotomy in the same sitting, which had resulted in cessation of tremor. The time of performance of the manual tasks diminished significantly in all cases in both groups (Student's t-test: p<0.0001). No complications developed following pallidotomy. Pallido-thalamotomy caused transient adverse effects in two patients, and one patient developed permanent adverse effects such as dysarthria and dysequilibrium. Significant improvements were observed in the speed of handwriting and drawing in both groups, but pallido-thalamotomy was accompanied with complications.
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PMID:Ablative stereotactic surgery improves manual performance time in Parkinson's disease. 1654 84

The safety and efficacy of subthalamic nucleus (STN) deep brain stimulation (DBS) in patients who have had a previous unilateral pallidotomy is not clear. We identified 10 patients (9 male) at the Baylor College of Medicine Parkinson's Disease Center who underwent STN DBS after prior unilateral pallidotomy. Demographics, efficacy as determined by off Unified Parkinson's Disease Rating Scale (UPDRS) part III scores, and levodopa equivalent dosing were analyzed. We then compared these to an age- and sex-matched group of 25 DBS patients who had no prior pallidotomy. After their initial pallidotomy (mean age, 51.8 +/- 10.8 years), the mean UPDRS motor off medicine scores improved from 51.3 +/- 14.3 to 34.9 +/- 12.8, and the UPDRS dyskinesia score improved from 1.8 +/- 1.0 to 0.8 +/- 0.7. Their STN DBS off UPDRS motor scores (mean age, 56.0 +/- 10.2 years) improved by 16.0% from 53.1 +/- 9.7 (range, 42-68) to 44.6 +/- 11.1 (range, 25-67). In contrast, the UPDRS off motor scores in a control group of 25 DBS patients improved by 49.9%, from 49.7 +/- 11.1 to 25.7 +/- 18.9, (16.0% vs. 49.9%; P < 0.001). Changes in UPDRS dyskinesia scores were similar in both groups. AE thought to be related to the STN DBS following pallidotomy included worse dysarthria (three) and worse balance (two). STN DBS patients with prior pallidotomy had less improvement in UPDRS off motor score compared to other STN DBS patients, despite relatively good outcomes immediately after their pallidotomy. This may be partially due to a selection bias, but it may also indicate that prior pallidotomy is a negative predictor of outcome of STN DBS and should be considered in patient selection.
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PMID:Subthalamic deep brain stimulation in patients with a previous pallidotomy. 1667 6

Parkinson's disease is a progressive neurological disorder characterized by tremor, bradykinesia, rigidity, gait and postural instability and a variety of nonmotor symptoms. While these and other motor signs typically improve with levodopa, the so-called axial signs, such as dysarthria, dysphagia, postural instability and freezing, and most nonmotor signs, such as depression, cognitive decline and dysautonomia, usually do not respond satisfactorily to levodopa. Furthermore, the use of levodopa may be limited by the development of motor fluctuations, dyskinesias and other adverse effects. This manuscript reviews the medical management of advanced Parkinson's disease, focusing on the treatment of motor fluctuations and dyskinesias and of nonmotor and nonlevodopa responsive symptoms.
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PMID:Treatment of advanced Parkinson's disease. 1689 46

Chronic bilateral high-frequency stimulation of the subthalamic nucleus (STN) is an alternative treatment for disabling forms of Parkinson's disease when on-off fluctuations and levodopa-induced dyskinesias compromise patients' quality of life. The aim of this study was to assess the evolution of side-effects during the first year of follow-up and search for clinical predictive factors accounting for their occurrence. We compared the frequency of side-effects at 3 and 12 months after surgery in a cohort of 44 patients. The off-medication scores of Unified Parkinson's Disease Rating Scale (UPDRS) II, III, axial symptoms, disease duration and age at surgery were retained for correlation analysis. Dysarthria/hypophonia, weight gain and postural instability were the most frequent chronic side-effects. Whereas dysarthria/hypophonia remained stable over time, weight gain and postural instability increased during the first year post-op. High axial and UPDRS II scores at surgery were predictive of dysarthria/hypophonia. Age and axial score at surgery were positively correlated with postural instability. Despite the occurrence of side-effects, the benefit/side-effects ratio of STN stimulation was largely positive during the first year of follow-up. Age, intensity of axial symptoms and UDPRS II off-medication score before surgery are predictive factors of dysarthria/hypophonia and postural instability after surgery.
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PMID:Side-effects of subthalamic stimulation in Parkinson's disease: clinical evolution and predictive factors. 1693 Mar 62

This study investigates the importance of fundamental frequency (F0) as a perceptual cue for identification of vowel targets produced by speakers with Parkinson's disease (PD). It has been suggested in the literature that F0 is a redundant cue for vowel identification in highly intelligible speech. For speakers with dysarthria who are having difficulty with segmental and suprasegmental aspects of production which result in ambiguous or conflicting cues in the acoustic signal, F0 may have increased perceptual importance for accurate identification of vowel targets. In the present study, F0 contours for single-word targets produced in sentence level material by 20 speakers with PD and 20 control speakers were synthetically modified in several different ways (i.e., flattened and enhanced). Listener identification of vowel targets across the F0 conditions was recorded. The accuracy of vowel identification for the control group was not affected by the flattening of the F0 contour. For the speakers with PD, however, modification of the F0 contour (flattening or enhancing) affected the accuracy with which listeners identified certain vowels. Differences in vowel identification were found primarily for the front vowels /I, epsilon, ae/ along a high-low continuum.
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PMID:Fundamental frequency as a perceptual cue for vowel identification in speakers with Parkinson's disease. 1696 34


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