6 research outputs found
Upper and Lower Limb Movement Kinematics in Aging
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder associated with a premutation cytosine-guanine-guanine (CGG) trinucleotide repeat expansion of the FMR1 gene. FXTAS is estimated to be the most common single-gene form of ataxia in the aging population. Gait ataxia and intention tremor are the primary behavioral symptoms of FXTAS, though clinical evaluation of these symptoms often is subjective, contributing to difficulties in reliably differentiating individuals with FXTAS and asymptomatic premutation carriers. This study aimed to clarify the extent to which quantitative measures of gait and upper limb kinematics may serve as biobehavioral markers of FXTAS degeneration. Nineteen premutation carriers (aged 46-77 years), including 9 with possible, probable, or definite FXTAS and 16 sex- and IQ-matched healthy controls, completed tests of non-constrained walking and reaching while both standing (static reaching) and walking (dynamic reaching) to quantify gait and upper limb control, respectively. For the non-constrained walking task, participants wore reflective markers and walked at their preferred speed on a walkway. During the static reaching task, participants reached and lifted boxes of different sizes while standing. During the dynamic reaching task, participants walked to reach and lift the boxes. Movement kinematics were examined in relation to clinical ratings of neuromotor impairments and CGG repeat length. During non-constrained walking, individuals with FXTAS showed decreased stride lengths and stride velocities, increased percentages of double support time, and increased variabilities of cadence and center of mass relative to both asymptomatic premutation carriers and controls. While individuals with FXTAS did not show any static reaching differences relative to the other two groups, they showed multiple differences during dynamic reaching trials, including reduced maximum reaching velocity, prolonged acceleration time, and jerkier movement of the shoulder, elbow, and hand. Gait differences during non-constrained walking were associated with more severe clinically rated posture and gait symptoms. Reduced maximum reaching velocity and increased jerkiness during dynamic reaching were each related to more severe clinically rated kinetic dysfunction and overall neuromotor symptoms in FMR1 premutation carriers. Our findings suggest kinematic alterations consistent with gait ataxia and upper limb bradykinesia are each selectively present in individuals with FXTAS, but not asymptomatic aging premutation carriers. Consistent with neuropathological and magnetic resonance imaging (MRI) studies of FXTAS, these findings implicate cerebellar and basal ganglia degeneration associated with neuromotor decline. Our results showing associations between quantitative kinematic differences in FXTAS and clinical ratings suggest that objective assessments of gait and reaching behaviors may serve as critical and reliable targets for detecting FXTAS risk and monitoring progression
Upper and Lower Limb Movement Kinematics in Aging FMR1 Gene Premutation Carriers
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder associated with a premutation cytosine-guanine-guanine (CGG) trinucleotide repeat expansion of the FMR1 gene. FXTAS is estimated to be the most common single-gene form of ataxia in the aging population. Gait ataxia and intention tremor are the primary behavioral symptoms of FXTAS, though clinical evaluation of these symptoms often is subjective, contributing to difficulties in reliably differentiating individuals with FXTAS and asymptomatic premutation carriers. This study aimed to clarify the extent to which quantitative measures of gait and upper limb kinematics may serve as biobehavioral markers of FXTAS degeneration. Nineteen premutation carriers (aged 46–77 years), including 9 with possible, probable, or definite FXTAS and 16 sex- and IQ-matched healthy controls, completed tests of non-constrained walking and reaching while both standing (static reaching) and walking (dynamic reaching) to quantify gait and upper limb control, respectively. For the non-constrained walking task, participants wore reflective markers and walked at their preferred speed on a walkway. During the static reaching task, participants reached and lifted boxes of different sizes while standing. During the dynamic reaching task, participants walked to reach and lift the boxes. Movement kinematics were examined in relation to clinical ratings of neuromotor impairments and CGG repeat length. During non-constrained walking, individuals with FXTAS showed decreased stride lengths and stride velocities, increased percentages of double support time, and increased variabilities of cadence and center of mass relative to both asymptomatic premutation carriers and controls. While individuals with FXTAS did not show any static reaching differences relative to the other two groups, they showed multiple differences during dynamic reaching trials, including reduced maximum reaching velocity, prolonged acceleration time, and jerkier movement of the shoulder, elbow, and hand. Gait differences during non-constrained walking were associated with more severe clinically rated posture and gait symptoms. Reduced maximum reaching velocity and increased jerkiness during dynamic reaching were each related to more severe clinically rated kinetic dysfunction and overall neuromotor symptoms in FMR1 premutation carriers. Our findings suggest kinematic alterations consistent with gait ataxia and upper limb bradykinesia are each selectively present in individuals with FXTAS, but not asymptomatic aging premutation carriers. Consistent with neuropathological and magnetic resonance imaging (MRI) studies of FXTAS, these findings implicate cerebellar and basal ganglia degeneration associated with neuromotor decline. Our results showing associations between quantitative kinematic differences in FXTAS and clinical ratings suggest that objective assessments of gait and reaching behaviors may serve as critical and reliable targets for detecting FXTAS risk and monitoring progression
Exploring the contributing factors of success in department of defense schools : a literature review
Each year Department of Defense schools worldwide outscore most every state in the U.S. on the National Assessment of Education Progress test (Kingston, 2002). This literature review is a culmination of multiple research studies done on various facets of the Department of Defense Education Activity (DoDEA). It explores the contributing factors of success in DoDEA schools from a perspective of a potential new teacher applicant. This thesis begins with the history of DoDEA since its creation in World War II, and then leads into its chain of command, from the Secretary of Defense down to regional superintendents, school principals, and teachers. The adequate funding and financial resources of Do DEA are explained, along with the Community Strategic Plan, which is a set of guidelines that drives all school program decisions. School curriculum and instruction, professional development, and parent influence and the military\u27s corporate commitment to excellent are also discussed. Perhaps, more than any other factor, the community influence and support for academic excellence contribute to its sustained success
Making good on a call to expand method choice for young people - Turning rhetoric into reality for addressing Sustainable Development Goal Three
Abstract Background Investments in the nearly two billion young people, aged 10–24 years, in the world today are necessary to meet global development commitments, specifically the Sustainable Development Goals and Ending Preventable Child and Maternal Deaths. More than 12 million married and unmarried adolescents (aged 15–19) will give birth in 2016. Complications of pregnancy and childbirth are the second leading cause of death among 15–19 year-old women and early childbearing can significantly curtail social and economic prospects for young women. Facilitating the ability of sexually active young people to choose and effectively use a satisfactory contraceptive method will ensure they can exercise their right to prevent, delay or space pregnancy. The Global Consensus Statement, “Expanding Contraceptive Choice for Adolescents and Youth to Include Long Acting and Reversible Contraception” provides evidence on the safety and effectiveness of LARCs for young people. Three inter-dependent actions linking advocacy and policy (advocating for policy and guideline revisions); supply (improving quality and accessibility of an expanded method choice) and an enabling environment (social norms and comprehensive reproductive health information) are suggested as vital to achieving full access and full choice for all sexually active young people. Identified approaches include national advocacy addressing policy guidelines and standard operating procedures that guide providers in the provision of age and developmentally appropriate contraceptive services; pre-service and in-service training for health care providers to be able to effectively communicate and counsel young people, including dispelling myths and misconceptions around LARCs; and partnering with young people to design appropriate, contextually-relevant, and effective strategies to increase their self-efficacy and, at the community level, address broader social norms to dispel stigma and discrimination. Conclusion An immediate call to action for collaborative and coordinated global, regional and national efforts that enable full access and full choice for all young people is paramount to achieve their reproductive health intentions and the Sustainable Development Goal targets
Making good on a call to expand method choice for young people - Turning rhetoric into reality for addressing Sustainable Development Goal Three
\u3ci\u3eDrosophila\u3c/i\u3e Muller F Elements Maintain a Distinct Set of Genomic Properties Over 40 Million Years of Evolution
The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu