The purpose of this qualitative descriptive study was to obtain information from adolescent siblings of children with Down syndrome (CWDS) regarding their perceptions of living with a child who has Down syndrome (DS). Twenty-three adolescents between 12 and 19 years of age who lived with a child who had DS and additional health problems including cardiac, endocrine, gastrointestinal, hematological, neurological, and behavioral conditions were interviewed individually. After examining the tape recorded interviews, major themes revealed both positive and negative aspects of living with a child with DS who has major health problems. However, overall the adolescents reflected more positive experiences than negative experiences. In addition, most adolescents interviewed said they would not change anything about their experience. One interesting finding was that most participants did not believe the child with DS would ever live independently, perhaps because of the additional health problems these CWDS have. Information gained from this study provides information for nurses and families to help better understand adolescent sibling perceptions about living with a CWDS so more appropriate and individualized nursing interventions can be provided for siblings and their families. This information can assist nurses in supporting similar families gain better coping skills, learn more about the impact of DS on families, and provide information on stress management and nursing interventions to support family growth and development especially for adolescents who have the added responsibility of caring for and living with a CWDS.

Thesis (Ed.D.)--Boston University / This study was conducted for the purpose of determining the effectiveness of a home-based motor activity program on children with Down syndrome 6 to 10 years of age. Twenty-six children with Down syndrome and their respective families participated in this twelve-week study. The Circles Of Learning instructional program was created, and fieldtested. The Test of Gross Motor Development (TGMD) provided base-line data for measures of progress in fundamental motor skills. Parents were instructed in how to teach locomotor skills and object control skills as measured by the TGMD. The methods required seven distinct activities: the creation of an instructional manual; recruitment and instruction of project assistants; identification and recruitment of the subjects and their families; pretest and posttest assessment of subjects; instructional training of parents; and the twelve week intervention. The comparison (C) group received the Handwriting Without Tears program during the 12 week intervention period. When compared with the (C) group, all subjects in the experimental (E) group showed statistically significant improvement in the acquisition of fundamental motor skills as measured by the TGMD. Four (E) group subjects improved to the "average" range for typically developing children. Ten of the 11 (E) group subjects continued to improved their demonstrated fundamental motor skill performance two weeks after the intervention, while one subject maintained his gains. Weekly parent comments during the intervention gave testimony to the effectiveness of the intervention supporting primary and secondary gains for the subjects. Parents reported that interactions between family members and the subjects increased and fundamental motor skills improved during spontaneous unstructured play and during organized activities at home and at school. This study challenges the previous research suggesting children with Down syndrome need specialized motor development programs. Furthermore, this study demonstrates that the acquisition of fundamental motor skills for children with Down syndrome can be accelerated.

Identifying factors that influence physical activity (PA) among individuals with Down syndrome (DS) is essential for PA promotion. Insight can be gained from guardians and health professionals. The purpose was to compare guardians and health professional perspectives on facilitators and barriers of PA in individuals with DS. Interviews were conducted with 11 guardians (5 mothers, 4 fathers, 2 legal guardians) and 11 professionals (4 PA specialists, 3 physical therapists, 4 occupational therapists). Grounded Theory was applied to data analysis. Barriers and facilitators fit the levels of the Ecological Model of Health Behavior: (a) Intrapersonal (perceived rewards); (b) Interpersonal (interaction); (c) Community (availability of programs); (d) Organizational (school systems); (e) Policy (education). Guardians and professionals agreed on the importance of enjoyment, interaction, and programs to promote PA. Differences were found among organizational and policy levels. PA in persons with DS is influenced by interactions between individual and environmental factors.

There is a need to examine the difference in the relationship between oxygen uptake (VO2) and output from hip- and wrist-worn accelerometers in adults with Down syndrome (DS). The purpose of this study is to identify if that relationship is different between adults with and without DS. Hip- and wrist-worn accelerometer accuracy was also assessed. The sample included 16 adults with DS (10 men; age 31±15 years) and 19 adults without DS (10 men; age 24±6 years). We measured VO2 with a portable spirometer and accelerometer output (Vector Magnitude [VM]) with a hip- and a wrist-worn accelerometer. VM and group were significant predictors of VO2 (p?0.021). BMI became a significant predictor in the second model and DS was no longer significant for both accelerometer models. The Bland-Altman plots indicated nearly zero mean error for both groups. Hip-worn accelerometers showed greater accuracy, and showed less error based on 95% confidence intervals.

Indiana University-Purdue University Indianapolis (IUPUI) / Down syndrome (DS) is a genetic condition caused by the triplication of human chromosome 21 and presents with many phenotypes including decreased brain size, hypocellularity in the brain, and assorted ocular phenotypes. Some of the ocular phenotypes seen are increased risk of cataracts, accommodation difficulties, increased risk of refractive errors, and increased retinal thickness. The Ts65Dn mouse model of DS is a classically used mouse model as it presents a number of phenotypes also seen in those with DS. Some of these phenotypes include decreased brain volume, abnormal synaptic plasticity, and ocular phenotypes. These ocular phenotypes include decreased visual acuity, cataracts, and increased retinal thickness. The Ts65Dn mouse model is trisomic for Dyrk1a, a gene of interest in DS research. We hypothesize that there will be a genotypic and sex effect of retinal thickness and retinal ganglion cell (RGC) count at postnatal day 15 in the Ts65Dn mouse model of DS. Retinal slices were taken from male and female trisomic and euploid Ts65Dn mice at P15 and fluorescently labeled for RGCs and bipolar cells via immunohistochemistry. The retinas were measured for total retinal thickness and RNA-binding protein (RBPMS) positive cells in the RGC layer were counted. There was no genotypic or sex effect when comparing retinal thickness in trisomic mice as compared to euploid mice. There was a genotypic effect of RBPMS positive cell count in which the trisomic mice had a higher number of RBPMS positive cells than euploid mice. Increased retinal thickness along with increased RGC number have both been implicated with decreased apoptosis in the retina. In the Ts65Dn mouse model along with in individuals with DS, this could be due to an increase in DYRK1A protein levels reducing apoptosis. In future studies, determining DYRK1A’s influence in retinal thickness and RGC number could result in a treatment for overactive DYRK1A that could normalize retinal thickness and RGC number in those with DS.

<p dir="ltr">Down syndrome (DS) arises from the triplication of human chromosome 21 (Hsa21), leading to a spectrum of phenotypes characterized by neurodevelopmental and cognitive abnormalities. The Ts65Dn mouse model emulates DS by harboring three copies of genes found on Hsa21 resulting in trisomy 21 (Ts21)- like traits, including disruptions in neuronal pathways, delays in sensorimotor and behavior milestones, and deficits in learning and memory tasks. There is no cure for DS and available therapies primarily address symptoms stemming from Ts21-associated phenotypes. <i>DYRK1A</i>, a gene triplicated in Ts21, has a pivotal role in pathways of neurodevelopment and has been a focus of inhibition treatment research aimed at preempting abnormal brain phenotypes. This study aimed to find a point of substantial <i>Dyrk1a </i>expression dysregulation during a period of critical neonatal neurodevelopment and employ targeted pharmacological and genetic knockdown methods to alleviate the presence or severity of characteristically abnormal brain and behavior phenotypes. The hypothesis of this study was that administering a targeted intervention prior to a point of known overexpression in trisomic pups would ameliorate molecular, sensorimotor, and neurobehavioral deficits, redirecting growth trajectories of Ts65Dn neonatal pups towards more neurotypical outcomes. To test this hypothesis, the spatiotemporal pattern of DYRK1A expression was quantified during the first three weeks of neonatal development across the hippocampus, cerebral cortex, and cerebellum of the Ts65Dn mouse model and found to fluctuate according to the genotype, age, sex, and brain region of the subject. <i>Dyrk1a </i>protein and mRNA expression levels were delineated in trisomic animals by age, exploring the correlation between expression and age, sex, genotype, and brain region. Next a constitutive <i>Dyrk1a </i>knockdown model was integrated with the Ts65Dn model to investigate the impact of gene copy number reduction on protein and mRNA expression levels during phases of known DYRK1A dysregulation. On postnatal day 6, protein expression was rescued in all three brain regions of male animals but was rescued only in the cerebellum of females. There were no significant differences in mRNA transcript levels in either sex at this age. Finally, genetic elements were introduced into the Ts65Dn model to facilitate a spatiotemporally controlled functional reduction of <i>Dyrk1a</i> and discern how the timing of gene copy number reduction affects molecular and neurobehavioral development in a trisomic system. Results from these studies suggest that only functionally reducing <i>Dyrk1a </i>gene copy number on the day of birth is not sufficient to rescue the majority of deficits and delays present in the Ts65Dn mouse model of DS. These findings significantly enhance the understanding of trisomic <i>Dyrk1a </i>expression dynamics during neonatal development and shed light on tailored therapeutic approaches to modulate intrinsic DS characteristics based on age, sex, and phenotypic considerations.</p>

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.

Thesis (M.S.)--University of Michigan, 1983.

Doktoravhandling--Copenhagen. / Bibliography: p. 97-[100].

Thesis (M.S.)--University of Michigan, 1983.