Matching Items (31)
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- All Subjects: Down syndrome
- Creators: Ringenbach, Shannon
- Creators: School of International Letters and Cultures
- Creators: Bosch, Pamela
- Creators: Der Ananian, Cheryl
Description
Down syndrome (DS) is a common genetic developmental disorder characterized by the trisomy of chromosome 21 (Hsa21). All individuals with DS have some kind of intellectual disability, associated with dysfunction in cognition-related structures, including the frontal cortex. Studies have examined developmental changes in the frontal cortex during prenatal stages in DS, however little is known about cortical lamination and neuronal differentiation in postnatal periods in this neurodevelopmental disorder. Therefore, we examined the quantitative and qualitative distribution of neuronal profiles containing the neuronal migration protein doublecortin (DCX), the non-phosphorylated high-molecular-weight neurofilament SMI-32, the calcium-binding proteins calbindin D-28K (Calb), calretinin (Calr), and parvalbumin (Parv), as well as human β-amyloid and APP (6E10), Aβ1-42, and phospho-tau (CP-13) in the supragranular (SG, II/III) and infragranular (IG, V/VI) layers in the DS postnatal frontal cortex compared to neurotypically developing (NTD) controls from ages 28 weeks to 196.4 weeks using immunohistochemistry. Furthermore, cortical lamination was evaluated using thionin, a Nissl stain. We found DCX-immunoreactive (-ir) cells in both the SG and IG layers in younger cases, but not in the oldest cases in both groups. Strong expression of SMI-32 immunoreactivity was observed in pyramidal cells in layers III and V in the oldest cases in both groups, however SMI-32-ir cells appeared much earlier in NTD compared to DS. We found small and fusiform Calb-ir cells in the younger cases (28 to 44 weeks), while in the oldest cases, Calb immunoreactivity was also found in pyramidal cells. Calr-ir cells appeared earlier in DS at 32 weeks compared to NTD at 44 weeks, however both groups showed large bipolar fusiform-shaped Calr-ir cells in the oldest cases. Diffuse APP/Aβ-ir plaque-like accumulations were found in the frontal cortex grey and white matter at all ages, but no Aβ1-42 immunoreactivity was detected in any case. Furthermore, neuropil (but not cellular) granular CP-13 immunostaining was seen in layer I only at 41 weeks NTD and 33 weeks DS. Cell counts show a significantly higher cell number in SG compared to IG for all the neuronal markers in both groups, except in Calb and SMI-32. In NTD, age and brain weight showed the strongest correlations with all cellular counts, except in thionin where DS had a stronger negative correlation with age and brain weight compared to NTD. In addition, height and body weight showed a strong negative correlation in NTD with the migration and neurogenesis marker DCX. These findings suggest that trisomy 21 affects the postnatal frontal cortex lamination, neuronal migration<br/>eurogenesis, and differentiation of projection pyramidal cells and interneurons, which contribute to the disruption of the local and projection inhibitory and excitatory circuitries that may underlie the cognitive disabilities in DS.
ContributorsUtagawa, Emma Christina (Author) / Penkrot, Tonya (Thesis director) / Perez, Sylvia (Committee member) / Shafernak, Kristian (Committee member) / College of Health Solutions (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The purpose of our study was to examine the effectiveness of a cycling intervention on body composition in adolescents with Down syndrome (DS). Participants completed one of three interventions over eight consecutive weeks. The interventions were: 1) Voluntary Cycling (VC), in which participants cycled at their self-selected pedaling rate 2) Assisted Cycling (AC), in which the participants' voluntary pedaling rates were assisted with a motor to ensure the maintenance of 80 rpms. 3) No cycling (NC), in which the participants acted as controls. Participants in the AC intervention did not decrease body fat or increase lean body mass however they did maintain these measures during the intervention as compared to the VC and NO participants who increased body fat and decreased lean body mass. These statistics were not exactly as expected nor were they statistically significant. Future research will try to replicate this data with statistically significant values for more cycling adolescents with DS using more randomized intervention groups.
ContributorsBennett, Kristen Leigh (Author) / Ringenbach, Shannon (Thesis director) / Brown, Steven (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This study examines cognitive planning in adolescents with Down syndrome (DS) following an 8-week assisted cycling therapy intervention. Forty-three participants were randomly assigned to assisted cycling (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), voluntary cycling (VC) (self-selected cadence), and no cycling (NC) control group. Both AC and VC rode a stationary bicycle three times/week, 30 minutes/session, for eight weeks in duration. Participants completed cognitive testing that assessed cognitive planning at the beginning (i.e., pretest) and end (i.e., posttest) of the 8-week intervention. Consistent with our hypothesis, the results showed that cognitive planning improved following eight weeks of cycling for the AC group. The same results were not seen for individuals in the VC or NC groups. Our results suggest that assisted cycling therapy may induce permanent changes in the prefrontal cortex in adolescents with DS.
ContributorsMillar, Kelsey Leann (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This study examines the effectiveness of two modes of exercise on depression in adolescents with Down syndrome (DS). Thirty nine participants were randomly divided into a voluntary cycling group (VC) (i.e., self-selected cadence), an assisted cycling group (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), or a no exercise group (NC). In each cycling intervention the participant completed 30 minute cycling sessions, three times per week for a total of eight weeks. The Children's Depression Inventory II was administered prior to cycling (i.e., pretest) and after the eight week intervention (i.e., posttest). Although the data did not reach conventional levels of statistical significance, the results of the study demonstrated partial support for our hypothesis that adolescents with DS showed improvements in depression as measured by the Children's Depression Inventory II following assisted cycling, but not following eight weeks of voluntary cycling. In other words, eight weeks of moderate AC exercise demonstrated a trend for improved depression in adolescents with DS.
ContributorsMcgownd, Shana Leah (Author) / Ringenbach, Shannon (Thesis director) / Youngstedt, Shawn (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Effects of Assisted Cycle Therapy on Short Term and Working Memory in Adolescents with Down Syndrome
Description
To examine the effect of an 8-week cycling intervention on short term and working memory in adolescents with Down syndrome (DS), participants were divided into Assisted Cycling Therapy (ACT), Voluntary Cycling (VC), or No Cycling (NC) groups. Forward and backward digit span assessments were administered prior to and after the intervention to evaluate short term and working memory respectively. 8 weeks of exercise via ACT showed a trend toward conventional levels of significance in the number of levels completed in the backward direction.
ContributorsSandoval-Menendez, Amber Melanie (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This study examined the effect of an 8-week exercise intervention on functional exercise capacity in adolescents with Down syndrome (DS). Forty participants were randomly assigned to one of three groups: assisted cycling (ACT) (n = 17) where participants experienced at least a 35% increase in their voluntary cycling speed through the use of a motor, voluntary cycling (VC) (n = 15) where participants cycled at a self-selected cadence, and no cycling (NC) (n = 8) where participants did not participate in any cycling intervention. In each cycling intervention, each participant completed three, 30 minute cycling sessions per week for a total of eight weeks. The Six-Minute Walk Test (6MWT) was administered prior to and after the 8-week intervention in pre-test and post-test assessment sessions, respectively. Our hypothesis was somewhat supported in that functional exercise capacity improved after ACT as measured by an increase in total number of laps walked, total distance walked, and average walking speed during the 6MWT, when compared to VC or NC.
ContributorsCook, Megan Rey (Author) / Ringenbach, Shannon (Thesis director) / Huberty, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
This study examines cognitive and motor function in adolescents with Down syndrome (DS) following an 8-week assisted cycling therapy intervention. Forty-four participants were randomly assigned to three groups consisting of an assisted cycling (AC) (i.e., exercise accomplished through the use of a motor), a voluntary cycling (VC) (self-selected cadence), and a no cycling (NC) control group. Both ACT and VC groups rode a stationary bicycle for three 30-minute sessions a week, for a total of eight weeks. Participants completed cognitive testing that assessed information processing and manual dexterity at the beginning and at the end of the 8-week intervention. Consistent with our hypothesis, the results showed that information processing and manual dexterity improved following 8 weeks of cycling for the ACT group. These results were not seen for individuals in the voluntary and non-exercise groups. Our results suggest that assisted cycling therapy may induce permanent changes in the prefrontal cortex in adolescents with DS.
ContributorsJimenez, Andrew (Author) / Ringenbach, Shannon (Thesis director) / Kulinna, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Previous research has found improvements in motor and cognitive measures following Assisted Cycle Therapy (AC) in adolescence with Down syndrome (DS). Our study investigated whether we would find improvements in older adults with DS on measures of leisure physical activity (GLTEQ) and sleep, which are early indicators of Alzheimer's disease (AD) in persons with Down syndrome. This study consisted of eight participants with Down syndrome between 31 and 51 years old that cycled for 30 minutes 3 x/week for eight weeks either at their voluntary cycling rate (VC) or approximately 35% faster with the help of a mechanical motor (AC). We predicted that, based on pilot data (Gomez, 2015), GLTEQ would either maintain or improve after AC, but would decrease after VC and would stay the same after NC. We predicted that the sleep score may improve after both VC or AC or it may improve more after VC than AC based on pilot data related to leisure activity. Our results were consistent with our prediction that GLTEQ will either maintain or improve after AC but will decrease after VC. Our results were not consistent with our prediction that sleep may improve after both VC or AC or it may improve more after VC than AC, possibly because we did not pre-screen for sleep disorders. Future research should focus on recruiting more participants and using both objective and subjective measures of sleep and physical activity to improve the efficacy of the study.
ContributorsParker, Lucas Maury (Author) / Ringenbach, Shannon (Thesis director) / Buman, Matthew (Committee member) / Holzapfel, Simon (Committee member) / School of Social and Behavioral Sciences (Contributor) / School of Nutrition and Health Promotion (Contributor) / College of Public Service and Community Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This study examines the effectiveness of two modes of exercise on self-efficacy (SE) in adolescents with Down syndrome (DS). Thirty-nine participants were randomly divided into a voluntary cycling group (VC) (i.e., self-selected cadence), an assisted cycling group (ACT) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), or a no exercise group (NC). In each cycling intervention the participant completed 30 minute cycling sessions, three times per week for a total of eight weeks. Two subsets of the Physical Activity and Self Efficacy Survey were administered prior to cycling (i.e., pretest) and after the eight week intervention (i.e., post-test). The results were consistent with the hypothesis that self-efficacy would improve after ACT, however there was not improvement after the VC condition as hypothesized. It was also hypothesized that exercise perception would improve following the ACT intervention; execise perception showed a trend of improvement after ACT, but the data did not reach significance. Limitations include the wide variability of the DS population. This limitation is responsible for the variation in mental age seen in the intervention groups and could be responsible for the non-significance of the exercise perception data. To generalize our results for parents, therapists, teachers, etc., our recommendation is for persons with DS to participate in physical activity that is easy for them at first \u2014 a simplified sport or active game, assisted cycling, brisk walking \u2014 so that they have a positive experience with exercise. Showing individuals with DS that they can be proficient exercisers will likely improve their self-efficacy and motivate them to engage in more PA over time. In conclusion, eight weeks of moderate ACT exercise demonstrated a significant trend for improved self-efficacy in adolescents with DS.
ContributorsWallace, Kellie Carter (Author) / Ringenbach, Shannon (Thesis director) / Youngstedt, Shawn (Committee member) / Hoffner, Kristin (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
The aim of this study is to understand the affects of grip strength and manual dexterity in activities of daily living (ADL) in persons with Down syndrome (DS). This is important because it could help with future interventions that are focused around improving related disadvantages in this particular population. Ten participants with DS performed the manual dexterity tests (i.e., Purdue Pegboard) and measured their grip strength with a hydraulic dynamometer. Overall, grip strength was lower than the average for the typical population and was reduced after aeorbic exercise. Improvements, however, were found in their manual dexterity from pre-test to post-test. This indicates that the assisted moderate intensity exercise intervention helped their dexterity performance. The improvements in dexterity are consistent with previous research conducted by Ringenbach et al. (2007). These results suggest that a moderate intensity treadmill walking exercise intervention can increase precision and efficiency in dexterity in persons with Down syndrome, however their grip force production may be stimulated by another means.
ContributorsSemper, Logan (Author) / Ringenbach, Shannon (Thesis director) / Kulinna, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2012-12