Biomedical subjects

Sarah L Westcott

Publications and source records attributed to Sarah L Westcott.

8 recordsLinked to original sources

PubMed2006

Biochemical analysis of a DNA replication origin in the archaeon Aeropyrum pernix.

We have characterised the interaction of the Aeropyrum pernix origin recognition complex proteins (ORC1 and ORC2) with DNA using DNase I footprinting. Each protein binds upstream of its respective gene. However, ORC1 protein alone interacts more tightly with an additional region containing multiple origin recognition box (ORB) sites that we show to be a replication origin. At this origin, there are four ORB elements disposed either side of an A+T-rich region. An ORC1 protein dimer binds at each of these ORB sites. Once all four ORB sites have bound ORC1 protein, there is a transition to a higher-order assembly with a defined alteration in topology and superhelicity. Furthermore, after this transition, the A+T-rich region becomes sensitive to digestion by DNase I and P1 nuclease, revealing that the transition promotes distortion of the DNA in this region, presumably as a prelude to loading of MCM helicase.

Aeropyrum↗

PubMed2006

Physical therapy clinical management recommendations for children with cerebral palsy - spastic diplegia: achieving functional mobility outcomes.

The purpose of this special report is to present recommendations for the clinical management of children with cerebral palsy, spastic diplegia when increased functional mobility is the identified outcome. These recommendations provide a framework that allows physical therapists to increase their accountability and promote effective interventions for improved patient outcomes. The key components of this special report on clinical management are: a) the Major Recommendations that provide the background and evidence for clinical management; b) a flow chart to assist in clinical decision-making; and c) a Table of Tests and Measures for information on useful tools in the management of children with spastic diplegia. These recommendations are suggestions for clinical management, not an all-inclusive document on physical therapy for children with cerebral palsy. These recommendations may help therapists develop systematic approaches to service delivery and documentation.

Adolescent↗

PubMed2005

Exploring physical therapy clinical decision making for children with spastic diplegia: survey of pediatric practice.

PURPOSE: The purpose of this special interest report is to describe the outcomes of a research round table discussion regarding the physical therapy management of mobility for children with spastic diplegia. DESCRIPTION: Sixty-two pediatric physical therapists and physical therapists assistants participated in focus groups during the Research Round Table at the American Physical Therapy Association (APTA) 1999 Combined Sections Meeting. A case description of a child with spastic diplegia and guiding questions were used to facilitate discussion. SUMMARY OF EXPERIENCE: Common practices in patient management across the child's life-span emerged from the discussion. Practices in examination, evaluation and prognosis, and intervention differed depending on the age and function of the child and the family's needs. In general, therapists reported that younger children receive examinations that include standardized tests of development and ongoing intervention with a frequency of one to five times per week. In contrast, older children receive therapy services on an episodic basis that address their specific needs. The elements of patient management served as a useful framework for exploring decision making. IMPORTANCE TO PEDIATRIC PHYSICAL THERAPY: The information compiled from this project needs to be validated through systematic inquiry. Therapists may, however, use the practices reported here to reflect on their clinical decision making and to identify questions for further exploration. This descriptive document is the first step in the development of a guideline for evidence-based practice. The development of such a clinical guideline could serve as an education tool for novice therapists, a program evaluation tool to ensure quality care, and a foundation for future research to promote evidence-based practice.

Adolescent↗

PubMed2005

Responsiveness of the Test of Infant Motor Performance (TIMP) in infants born preterm.

PURPOSE: The responsiveness of the Test of Infant Motor Performance (TIMP) was examined in infants born preterm. Infant variables predictive of changes in TIMP scores were also identified. METHODS: Twenty-five infants born <or=30 weeks' gestational age were assigned a risk score and administered the TIMP at 32 and 36 weeks postconceptional age (PCA). Paired t-tests and analyses of variance examined differences between TIMP scores across time and between groups. Correlations and regression analyses determined the relationship between infant variables and TIMP score changes. RESULTS: TIMP scores significantly increased between 32 and 36 weeks PCA. A significant effect of time for risk groups was found. No significant correlations between infant variables and TIMP score changes were revealed. CONCLUSIONS: The TIMP was responsive to changes in infants born preterm but did not discriminate based on risk classification. The infant variables did not predict changes in TIMP scores. Further research with a larger sample size is warranted.

Developmental Disabilities↗

PubMed2005

Synthesis and luminescence of ZnMgS:Mn2+ nanoparticles.

Efficient green emission from ZnMgS:Mn2+ nanoparticles prepared by co-doping Mg2+ and Mn2+ ions into ZnS lattices has been observed. The synthesis is carried out in aqueous solution, followed by a post-annealing process, thus showing the features of less complexity, low cost, and easy incorporation of dopants. In comparison with the emission of ZnS:Mn2+ nanoparticles, which is located generally around 590 nm, the photoluminescence of ZnMgS:Mn2+ nanoparticles is blue-shifted by 14 nm in wavelength, leading to the enhanced green emission. The X-ray diffraction, electron spin resonance, and pressure dependent photoluminescence measurements suggest that the change of the crystal field caused by Mg2+ ionic doping and the lower symmetry in the nanoparticles may account for the blue-shift of the photoluminescence. The ZnMgS:Mn2+ nanoparticles with 1% Mn2+ doping exhibit the strongest luminescence, which could potentially meet the requirements for the construction of green light emitting diodes.

Crystallization↗

PubMed2004

Timed up and down stairs test: preliminary reliability and validity of a new measure of functional mobility.

PURPOSE: The reliability and validity of a new test, the Timed Up and Down Stairs (TUDS), were examined in children with and without cerebral palsy (CP). METHODS: A convenience sample of 47 children age eight to 14 years participated, 20 with CP and 27 with typical development (TD). Using intraclass correlation coefficients (ICC), interrater, intrarater, and test-retest reliability of the TUDS were examined by two raters simultaneously testing nine children, by one rater who then rescored at a later time a video of the testing of 24 children, and by one rater testing 25 children twice with a two-hour separation, respectively. Concurrent validity was examined using Spearman rank correlations between TUDS scores and performance on the Timed Up and Go (TUG), the Functional Reach Test (FRT), and a Timed One Legged Stance (TOLS), which were completed in a random order on all children. Construct validity was examined by correlation and Kruskal-Wallis analysis of variance of scores across ages and three functional level groups. RESULTS: The TUDS demonstrated excellent intrarater, interrater, and test-retest reliability [ICC (2,1) > or =0.94] and moderate to high concurrent validity (Spearman r(s) = 0.78, -0.57, and -0.77, with the TUG, FRT, and TOLS, respectively). Age accounted for 37% and 56% of the variance in the TUDS for the TD group and for the Gross Motor Function Classification Scale level I CP group, respectively. Significant differences in TUDS scores were found between all three functional level groups. CONCLUSION: The TUDS has adequate reliability and validity in children with and without CP and appears to complement current clinical measures of functional mobility and balance. Further investigations on across larger age ranges and samples are warranted.

Journal Article↗

PubMed2004

Postural control in children: implications for pediatric practice.

Based on a systems theory of motor control, reactive postural control (RPA) and anticipatory postural control (APA) in children are reviewed from several perspectives in order to develop an evidence-based intervention strategy for improving postural control in children with limitations in motor function. Research on development of postural control, postural control in children with specific motor disabilities, and interventions to improve postural control is analyzed. A strategy for intervention to improve postural control systems at the impairment and functional activity levels based on a systems theoretical perspective is presented. Suggestions for research to improve evidence for best practice are provided.

Child↗

PubMed2004

Muscle force and range of motion as predictors of standing balance in children with cerebral palsy.

Children with cerebral palsy frequently receive therapeutic intervention to remediate standing balance deficits. Evaluation of the impairments associated with poor balance could facilitate more effective treatment programs. This study evaluated the relationship between lower extremity force production, range of motion and standing balance in thirty-five children between the ages of 6 and 14 years of age with spastic cerebral palsy. Standing balance was evaluated using the Pediatric Clinical Test of Sensory Interaction (P-CTSIB). Hand-held dynamometry was used to assess force production and goniometry was used to assess range of motion. The results indicated that force production and range of motion are highly related to standing balance. Blocked, hierarchical multiple regression analysis revealed that force production explained 41% of the variance in P-CTSIB scores in this sample, while range of motion explained an additional 13%. Therefore, the total variance explained by these variables was 54%. Results of this study suggest that impairment level testing may allow the development of more effective individualized intervention programs to remediate balance deficits. Clinical suggestions are provided.

Adolescent↗