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Introduction A broad range of subjective and objective assessments have been used to assess balance confidence and balance control in persons with Parkinson's disease (PD). However, little is known about the relationship between self-perceived balance confidence and actual balance control in PD. The purpose of this investigation was to determine the relationship between self-perceived balance confidence and objectively measured static/dynamic balance control abilities. Methods Forty-four individuals with PD participated in the study. Patients were stratified into 2 groups based on the modified Hoehn and Yahr (H&Y) disability score: early stage, H&Y≤2.0 and moderate stage, H&Y ≥2.5. All participants completed the activities-specific balance confidence (ABC) scale and performed standing balance and gait initiation tasks to assess static and dynamic balance control. The center of pressure (COP) sway (CE95%Sway) during static balance and the peak distance between the projections of the COP and the center of mass (COM) in the transverse plane (COPCOM) during gait initiation were calculated. Pearson correlation analyses were conducted relating the ABC score and CE95%Sway and COPCOM. Results For early stage PD, there was a moderate correlation between ABC score and CE95 %Sway (r=-0.56, R2=0.32, p=0.002), while no significant correlation was found between ABC score and COPCOM (r=-0.24, R2=0.06, p=0.227). For moderate stage PD, there was a moderate correlation between ABC score and COPCOM (r=0.49, R2=0.24, p=0.044), while no correlation was found between ABC score and CE95%Sway (r=-0.19, R2=0.04, p=0.478). Conclusion Individuals with different disease severities showed different relationships between balance confidence and actual static/dynamic balance control.

The reduced ankle moments during ADL are indicative of deficits in muscular capabilities in those with PD. Moreover, PD caused a redistribution of joint torques, such that PD participants used their hip extensors more and ankle plantarflexors less.

Persons with Parkinson’s disease (PD) are typically more susceptible than healthy adults to impaired performance when two tasks (dual task interference) are performed simultaneously. This limitation has by many experts been attributed to limitations in cognitive resources. Nearly all studies of dual task performance in PD employ walking or balance-based motor tasks, which are commonly impaired in PD. These tasks can be performed using a combination of one or two executive function tasks. The current study examined whether persons with PD would demonstrate greater dual task effects on cognition compared to healthy older adults (HOAs) during a concurrent cycling task. Participants with and without PD completed a battery of 12 cognitive tasks assessing visual and verbal processing in the following cognitive domains: speed of processing, controlled processing, working memory and executive function. Persons with PD exhibited impairments compared to healthy participants in select tasks (i.e., 0-Back, 2-Back and operation span). Further, both groups unexpectedly exhibited dual task facilitation of response times in visual tasks across cognitive domains, and improved verbal recall during an executive function task. Only one measure, 2-back, showed a speed-accuracy trade-off in the dual task. These results demonstrate that, when paired with a motor task in which they are not impaired, people with PD exhibit similar dual task effects on cognitive tasks as HOAs, even when these dual task effects are facilitative. More generally, these findings demonstrate that pairing cognitive tasks with cycling may actually improve cognitive performance which may have therapeutic relevance to cognitive decline associated with aging and PD pathology.

Red ginseng (RG) is the top-selling functional food in Korea, but is not recommended for use in hypertensive patients. This study was performed to determine the pharmacokinetic (PK) interaction between RG and amlodipine, an antihypertensive drug. RG (0, 0.5, 1, or 2 g/kg/d) was administered orally for 2 wk, and then amlodipine (10 mg/kg) was given orally, to Sprague-Dawley (SD) rats. Blood was collected at 0.08, 0.25, 1, 1.5, 2, 3, 6, 12, and 24 h after amlodipine administration. In intravenous (iv) study, RG (0, 1, or 2 g/kg/d) was administered orally to SD rats for 2 wk, followed by amlodipine (2 mg/kg) intravenously (iv). Plasma concentrations of amlodipine were analyzed using a high-pressure liquid chromatography-tandem mass system (LC-MS/MS). Oral administration of amlodipine produced an increase of time to maximum plasma concentration (tmax: 2.6, 4.1, 8.3, and 8.9 h at 0, 0.5, 1, and 2 g/kg/d, respectively), and a decrease of maximum plasma concentration (Cmax: 278.5, 212.4, 232.1, and 238.7 ng/ml at 0, 0.5, 1, and 2 g/kg/d, respectively.). However, the area under the concentration-time curve from time 0 to 24 h measurable concentration (AUC0-24 h was 3487.4, 2895.4, 3158.2, and 3495 ng/h/ml at 0, 0.5, 1, and 2 g/kg/d respectively) was not significantly changed among the different dose groups. Administration of amlodipine iv produced no significant changes in the apparent terminal half-life, volume of distribution, and AUC0-24 hr among the different dose groups. These results suggest that RG induced negligible influence on amlodipine pharmacokinetically in rats.