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)

In an effort to further our understanding of postural control in Parkinson's disease, we biomechanically evaluated the sit to walk task and its component tasks, sit to stand (STS) and gait initiation (GI) in 12 healthy older adults and 12 persons with Parkinson's disease (PWP). Performance was evaluated utilizing motion capture and two force plates. The major finding of this study was the inability of the PWP to appropriately merge the sequential component tasks (STS and GI) during STW. The PWP rose to nearly full height and had a longer delay between seat-off and gait initiation (P = 0.003 and P < 0.001, respectively) during STW. Additionally, the PWP moved with slower velocities leading to shorter, slower steps and decreased separation of the center of mass and center of pressure. These observed motor sequencing disturbances may be due to a disease related disability or limitations in proprioception, movement speed, muscular strength, and reduced general mobility.
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PMID:Dynamic postural stability during sit-to-walk transitions in Parkinson disease patients. 1846 85

Parkinson's disease is a frequent and major source of motor disability, for which physical therapies currently involve less than a third of ambulatory patients and are thus underutilized when compared to chemical and surgical treatments. However, dopaminergic therapies alone prove unable to prevent worsening of motor disability after a number of years. There is rising interest about physical neurorehabilitative therapy for Parkinson's disease, for its symptomatic therapeutic properties, but also for its potential neuroprotective effects in the light of compelling, recent animal literature. The approach to therapy in an individual patient may be governed at the most basic level by the disease stage. For moderate stages of Parkinson's disease (ambulatory patients who have retained a certain degree of physical independence), therapy may focus on the teaching of exercises to the patient: strategies established in controlled studies when used over few weeks periods include motor strengthening programs in the lower limb, high intensity aerobic exercises, attentional strategies using in particular verbal instruction sets, sensory cueing, active axial rotation exercises and high-number repetition of specific tasks. A randomized protocol will soon evaluate the concept of asymmetric motor training, combining a strengthening program in extensor, abductor, external rotator and supinator muscles and a stretching program in their antagonists. For advanced stages (individuals with compromised sit-to-stand, ambulation and significant disability), the therapeutic focus may shift to the teaching of compensation strategies to the patient and the caregiver, both to lessen the effects of motor impairment and to optimize safety. A number of these compensatory strategies are reviewed, some being validated in controlled protocols. In idiopathic Parkinson's disease, clinicians must continue evaluating the symptomatic and perhaps neuroprotective value of physical treatment strategies used over the long term. In atypical parkinsonism, physical treatments often remain the only realistic methods to improve motor behavior and reduce functional deficiencies. The relatively short duration of the effects of physical therapies implies that such programs be pursued over long periods of time, or repeated frequently, for their benefits to be maintained over time.
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PMID:[Neurorehabilitation in parkinsonian syndromes]. 2013 21

Timed Up and Go (TUG) test is a widely used clinical paradigm to evaluate balance and mobility. Although TUG includes several complex subcomponents, namely: sit-to-stand, gait, 180 degree turn, and turn-to-sit; the only outcome is the total time to perform the task. We have proposed an instrumented TUG, called iTUG, using portable inertial sensors to improve TUG in several ways: automatic detection and separation of subcomponents, detailed analysis of each one of them and a higher sensitivity than TUG. Twelve subjects in early stages of Parkinson's disease (PD) and 12 age matched control subjects were enrolled. Stopwatch measurements did not show a significant difference between the two groups. The iTUG, however, showed a significant difference in cadence between early PD and control subjects (111.1 +/- 6.2 versus 120.4 +/- 7.6 step/min, p < 0.006) as well as in angular velocity of arm-swing (123 +/- 32.0 versus 174.0+/-50.4 degrees/s, p < 0.005), turning duration (2.18 +/- 0.43 versus 1.79 +/- 0.27 s, p < 0.023), and time to perform turn-to-sits (2.96 +/- 0.68 versus 2.40 +/- 0.33 s, p < 0.023). By repeating the tests for a second time, the test-retest reliability of iTUG was also evaluated. Among the subcomponents of iTUG, gait, turning, and turn-to-sit were the most reliable and sit-to-stand was the least reliable.
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PMID:iTUG, a sensitive and reliable measure of mobility. 2038 4

This randomized controlled trial with blinded assessment aimed to determine the effect of a 6-month minimally supervised exercise program on fall risk factors in people with Parkinson's disease (PD). Forty-eight participants with PD who had fallen or were at risk of falling were randomized into exercise or control groups. The exercise group attended a monthly exercise class and exercised at home three times weekly. The intervention targeted leg muscle strength, balance, and freezing. The primary outcome measure was a PD falls risk score. The exercise group had no major adverse events and showed a greater improvement than the control group in the falls risk score, which was not statistically significant (between group mean difference = -7%, 95% CI -20 to 5, P = 0.26). There were statistically significant improvements in the exercise group compared with the control group for two secondary outcomes: Freezing of Gait Questionnaire (P = 0.03) and timed sit-to-stand (P = 0.03). There were statistically nonsignificant trends toward greater improvements in the exercise group for measures of muscle strength, walking, and fear of falling, but not for the measures of standing balance. Further investigation of the impact of exercise on falls in people with PD is warranted.
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PMID:The effects of an exercise program on fall risk factors in people with Parkinson's disease: a randomized controlled trial. 2062 34

Akathisia is a movement disorder characterized by an inner sense of unease, unrest, and dysphoria. It can result in an inability to stand, sit, or lie still, and an intense urge to move around. It is a common side effect of drugs, such as antipsychotics and serotonin selective reuptake inhibitors (SSRIs), but it also occurs spontaneously in patients with Parkinson's disease. Several lines of evidence suggest that akathisia can be attributed to low activity of dopaminergic projections from the midbrain to the ventral striatum. However, the exact pathophysiological mechanism of this extrapyramidal symptom remains unclear. This article describes a possible mechanism for drug-induced akathisia based on the differential functions of the core and shell portions of the nucleus accumbens. These ideas arise from contemporary concepts regarding the mechanisms of compulsion, impulsivity, and depression.
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PMID:The Mechanism of Drug-induced Akathsia. 2140 65

Orthostatic tremor (OT) is a rare syndrome characterized by unsteadiness on standing due to a high-frequency tremor involving the legs. Symptoms usually start in the sixth decade. Typically, the symptoms rapidly improve on sitting or walking, and the need to sit down or to move can be so strong that patients avoid situations where they have to stand still. A polygraphic recording of a fast and synchronous tremor of the legs, between 13 and 18Hz, is mandatory to confirm the diagnosis of OT. Many patients also suffer from tremor, often involving lower frequencies, of the face, hands, or trunk. Recent studies suggest that this is perhaps due to subharmonics of the high-frequency tremor spreading through the body. Most cases of OT seem to be idiopathic, though symptomatic forms have been occasionally described. Several cases of OT have been reported in Parkinson's disease (PD), either preceding the onset of OT or developing in long-standing PD, suggesting a dopaminergic control of the central oscillator, possibly in the posterior fossa. The response to treatment is often disappointing. Clonazepam is widely used as a first-line agent, but gabapentin and dopaminergic drugs may be helpful in some patients.
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PMID:Orthostatic tremor - a review. 2149 2

The aim of this study was to explore the electromyographic, kinetic and kinematic patterns during a partially restricted sit-to-stand task in subjects with and without Parkinson's disease (PD). If the trunk is partially restricted, different behavior of torques and muscle activities could be found and it can serve as a reference of the deterioration in the motor performance of subjects with PD. Fifteen subjects participated in this study and electromyography (EMG) activity of the tibialis anterior (TA), soleus (SO), vastus medialis oblique (VMO), biceps femoris (BF) and erector spinae (ES) were recorded and biomechanical variables were calculated during four phases of the movement. Subjects with PD showed more flexion at the ankle, knee and hip joints and increased knee and hip joint torques in comparison to healthy subjects in the final position. However, these joint torques can be explained by the differences in kinematic data. Also, the hip, knee and ankle joint torques were not different in the acceleration phase of movement. The use of a partially restricted sit-to-stand task in PD subjects with moderate involvement leads to the generation of joint torques similar to healthy subjects. This may have important implications for rehabilitation training in PD subjects.
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PMID:The effect of the partially restricted sit-to-stand task on biomechanical variables in subjects with and without Parkinson's disease. 2163 90

Neurodegenerative processes in Parkinson's disease (PD) particularly affect activities of daily living (ADL). Problems of patients with PD in sit-to-stand (STS) performance have been verified before, but not the effects of training on biomechanical measures of STS function. This pilot study aimed to analyse effects of 12 weeks of Nordic Walking training and severity of PD: healthy controls (CO), least (UPDRS A) and more severe (UPDRS B) affected PA on selected functional outcome measures. We expected improvements in PD similar to CO, with better performance of the unstable second phase and faster execution of the entire movement with higher velocities of centre of gravity (COG). 3D kinematics of 22 PD and 18 CO subjects before and after training, were recorded using a motion analysis system (Vicon, Oxford). We compared five outcome measures for STS in 11 PD and 11 CO, matched according to age, gender, height, and weight. Effects of Nordic Walking training were not statistically significant but indicated different patterns which depended on the values of patient's UPDRS score (part III, motor functions). Time required for STS performance increased and horizontal and vertical velocity of COG decreased in UPDRS B, which could be due to progression of PD during the training period. In contrast, UPDRS A showed similar effects as CO. The effects of Nordic Walking as an easy, economic and low-risk intervention on STS in PD depend on the degree of PD. Our findings may help scientists, patients, and therapists to adjust sport-physiological interventions.
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PMID:The influence of Nordic Walking training on sit-to-stand transfer in Parkinson patients. 2164 May 91

Gene expression analysis has become a ubiquitous tool for studying a wide range of human diseases. In a typical analysis we compare distinct phenotypic groups and attempt to identify genes that are, on average, significantly different between them. Here we describe an innovative approach to the analysis of gene expression data, one that identifies differences in expression variance between groups as an informative metric of the group phenotype. We find that genes with different expression variance profiles are not randomly distributed across cell signaling networks. Genes with low-expression variance, or higher constraint, are significantly more connected to other network members and tend to function as core members of signal transduction pathways. Genes with higher expression variance have fewer network connections and also tend to sit on the periphery of the cell. Using neural stem cells derived from patients suffering from Schizophrenia (SZ), Parkinson's disease (PD), and a healthy control group, we find marked differences in expression variance in cell signaling pathways that shed new light on potential mechanisms associated with these diverse neurological disorders. In particular, we find that expression variance of core networks in the SZ patient group was considerably constrained, while in contrast the PD patient group demonstrated much greater variance than expected. One hypothesis is that diminished variance in SZ patients corresponds to an increased degree of constraint in these pathways and a corresponding reduction in robustness of the stem cell networks. These results underscore the role that variation plays in biological systems and suggest that analysis of expression variance is far more important in disease than previously recognized. Furthermore, modeling patterns of variability in gene expression could fundamentally alter the way in which we think about how cellular networks are affected by disease processes.
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PMID:Variance of gene expression identifies altered network constraints in neurological disease. 2185 51

Many neurodegenerative diseases demonstrate abnormal mitochondrial morphology and biochemical dysfunction. Alterations are often systemic rather than brain-limited. Mitochondrial dysfunction may arise as a consequence of abnormal mitochondrial DNA, mutated nuclear proteins that interact directly or indirectly with mitochondria, or through unknown causes. In most cases it is unclear where mitochondria sit in relation to the overall disease cascades that ultimately causes neuronal dysfunction and death, and there is still controversy regarding the question of whether mitochondrial dysfunction is a necessary step in neurodegeneration. In this chapter we highlight and catalogue mitochondrial perturbations in some of the major neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). We consider data that suggest mitochondria may be critically involved in neurodegenerative disease neurodegeneration cascades.
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PMID:Mitochondria in neurodegeneration. 2239 27


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