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Biomedical subjects

D J Russell

Publications and source records attributed to D J Russell.

At least 19 recordsLinked to original sources
PubMed2003

Nutrient balance in the diet of spring calving, pasture-fed dairy cows.

AIMS: To report the nutrient composition of pastures fed to spring-calving dairy cows in the Manawatu region of New Zealand, and describe changes in the nutrient composition of these pastures over a 12-month period. Having done this we sought to: (1) compare the nutrient composition of the pasture offered with the nutrient requirements of spring-calving dairy cows; (2) identify periods when individual nutrient surpluses and deficits are likely; and, (3) identify nutrients that demonstrate a high level of variability between sampling occasions. METHODS: Seven farms took part in the study. Each farm was visited monthly from August 1996 to July 1997. Samples of pasture were taken at each visit and submitted for estimation of dry matter (DM), metabolisable energy (ME), crude protein (CP), non-structural carbohydrate (NSC), neutral detergent fibre (NDF), acid detergent fibre (ADF), calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), chlorine (Cl), sulphur (S), iron (Fe), copper (Cu) and zinc (Zn), and dietary cation-anion differences (DCAD). RESULTS: Sampled pastures were characterised by low to marginal ME, NSC, Ca, Mg, and Zn concentrations when compared with recommended dietary nutrient concentrations for lactating and non-lactating dairy cattle in New Zealand. Analyses revealed relatively high CP, NDF and K concentrations, and DCAD. CONCLUSIONS: These analyses identify broad trends in the nutrient balance of a pasture-only feeding regime and provide a useful reference for planning feed strategies for spring-calving, pasture-fed dairy herds in this region. Recommended changes to on-farm practice should be made after considering the whole farm system, rather than being made solely on the basis of perceived deficiencies or excesses of individual nutrients.

Journal Article↗
PubMed2001

Gross motor function of children with down syndrome: creation of motor growth curves.

OBJECTIVE: To create gross motor function growth curves for children with Down syndrome (DS) and to estimate the probability that motor functions are achieved by different ages. DESIGN: Nonlinear growth curve analysis by using a 2-parameter (rate, upper limit) model. SETTING: Early intervention programs, schools, and children's homes. PARTICIPANTS: One hundred twenty-one children with DS, ages 1 month to 6 years. MAIN OUTCOME MEASURES: Gross Motor Function Measure (GMFM) and severity of motor impairment. RESULTS: The curves for children with mild (n = 51) and moderate/severe (n = 70) impairment were characterized by a greater increase in GMFM scores during infancy and smaller increases as the children approached the predicted maximum score of 85.9 or 87.9. The estimated probability that a child would roll by 6 months was 51%; sit by 12 months, 78%; crawl by 18 months, 34%; walk by 24 months, 40%; and run, walk up stairs, and jump by 5 years, 45% to 52%. CONCLUSIONS: Children with DS require more time to learn movements as movement complexity increases. Impairment severity affected the rate but not the upper limit of motor function. The results have implications for counseling parents, making decisions about motor interventions, and anticipating the time frame for achievement of motor functions.

Child↗
PubMed2000

Improved scaling of the gross motor function measure for children with cerebral palsy: evidence of reliability and validity.

BACKGROUND AND PURPOSE: This study examined the reliability, validity, and responsiveness to change of measurements obtained with a 66-item version of the Gross Motor Function Measure (GMFM-66) developed using Rasch analysis. SUBJECTS AND METHODS: The validity of measurements obtained with the GMFM-66 was assessed by examining the hierarchy of items and the GMFM-66 scores for different groups of children from a stratified random community-based sample of 537 children with cerebral palsy (CP). A subset of 228 children who had been reassessed at 12 months was used to test the hypothesis that children who are young (<5 years of age) and have "mild" CP will demonstrate greater change in GMFM-66 scores than children who are older ((5 years of age) and whose CP is more severe. Data from an additional 19 children with CP who were assessed twice, one week apart, were used to examine test-retest reliability. RESULTS: The overall changes in GMFM-66 scores over 12 months and a time ( severity ( age interaction supported our hypotheses. Test-retest reliability was high (intraclass correlation coefficient=.99). CONCLUSION AND DISCUSSION: This study demonstrated that the GMFM-66 has good psychometric properties. By providing a hierarchical structure and interval scaling, the GMFM-66 can provide a better understanding of motor development for children with CP than the 88 item GMFM and can improve the scoring and interpretation of data obtained with the GMFM.

Activities of Daily Living↗
PubMed2000

Validation of a model of gross motor function for children with cerebral palsy.

BACKGROUND AND PURPOSE: Development of gross motor function in children with cerebral palsy (CP) has not been documented. The purposes of this study were to examine a model of gross motor function in children with CP and to apply the model to construct gross motor function curves for each of the 5 levels of the Gross Motor Function Classification System (GMFCS). SUBJECTS: A stratified sample of 586 children with CP, 1 to 12 years of age, who reside in Ontario, Canada, and are known to rehabilitation centers participated. METHODS: Subjects were classified using the GMFCS, and gross motor function was measured with the Gross Motor Function Measure (GMFM). Four models were examined to construct curves that described the nonlinear relationship between age and gross motor function. RESULTS: The model in which both the limit parameter (maximum GMFM score) and the rate parameter (rate at which the maximum GMFM score is approached) vary for each GMFCS level explained 83% of the variation in GMFM scores. The predicted maximum GMFM scores differed among the 5 curves (level I=96.8, level II=89.3, level III=61.3, level IV=36.1, and level V=12.9). The rate at which children at level II approached their maximum GMFM score was slower than the rates for levels I and III. The correlation between GMFCS levels and GMFM scores was (.91. Logistic regression, used to estimate the probability that children with CP are able to achieve gross motor milestones based on their GMFM total scores, suggests that distinctions between GMFCS levels are clinically meaningful. CONCLUSION AND DISCUSSION: Classification of children with CP based on functional abilities and limitations is predictive of gross motor function, whereas age alone is a poor predictor. Evaluation of gross motor function of children with CP by comparison with children of the same age and GMFCS level has implications for decision making and interpretation of intervention outcomes.

Activities of Daily Living↗
PubMed1996

A prospective randomized evaluation of a hygroscopic cervical dilator, Dilapan, in the preinduction ripening of patients undergoing induction of labor.

OBJECTIVE: Our purpose was to investigate the safety and efficacy of a synthetic intracervical hygroscopic dilator, Dilapan (Gynotech, Inc., Middlesex, N.J.), on ripening the cervix before medically indicated induction of labor. STUDY DESIGN: Two hundred forty patients with a Bishop score of < or = 4 were prospectively randomized to receive either preinduction synthetic hygroscopic dilators (n = 112) or no pretreatment (n = 128) before oxytocin induction. RESULTS: Compared with controls, the dilator group exhibited a significant change in median Bishop score, but there was no significant difference in length of labor (dilator 18.8 +/- 12.8 hours vs control 21.7 +/- 14.8 hours) or in the cesarean section rate (dilator 41/112 [36.6%] vs control 49/128 [38.3%]). Relative proportions of nulliparous and multiparous patients, infant weights, and cervical dilation at the time of cesarean section were not significantly different between groups. No adverse maternal or fetal effects could be attributed to use of the device. CONCLUSIONS: Preinduction cervical ripening with hygroscopic dilators does not shorten the length of labor or lower the cesarean section rate in patients undergoing induction of labor.

Abortifacient Agents↗
PubMed1995

The female pelvic mass. Diagnosis and management.

When a pelvic mass is encountered in a female patient, there are several tools available to the physician as diagnostic aids. The patient's age, history, and physical examination; diagnostic imaging studies; and laboratory tests can contribute valuable information to the diagnosis and management of the case. It is essential for today's physician to become familiar with these tools and to be able to direct management appropriately.

Abdomen↗
PubMed1995

Reliability of the Gross Motor Performance Measure.

BACKGROUND AND PURPOSE: The reporting of reliability coefficients and the method of their determination is expected of test developers. The purpose of this study was to estimate the interrater, intrarater, and test-retest reliability of the Gross Motor Performance Measure, a measure of quality of movement designed to accompany the Gross Motor Function Measure. SUBJECTS: Subjects were 28 children (25 with cerebral palsy, 2 nondisabled, 1 with head injury) between the ages of 1 and 10 years. METHODS: Reliability data were obtained from assessments of 19 therapists. RESULTS: Intraclass correlation coefficients for reliability varied from .92 to .96 for the total scores and from .84 to .94 for the five attribute scores. CONCLUSION AND DISCUSSION: When the Gross Motor Performance Measure was administered by therapists who are familiar with the Gross Motor Function Measure and had a 1-day training workshop, reliability of the total scores was above recommended minimums. Scores of single attributes were less reproducible.

Cerebral Palsy↗
PubMed1995

The Gross Motor Performance Measure: validity and responsiveness of a measure of quality of movement.

BACKGROUND AND PURPOSE: This article presents the results of a study to validate a measure of gross motor performance for its capacity to detect changes in the quality of movement in children with cerebral palsy aged 0 to 12 years. SUBJECTS AND METHODS: On two occasions, 4 to 6 months apart, physical therapists from three children's treatment centers assessed 106 children with cerebral palsy, 18 children who had sustained an acute head injury, and 29 nondisabled children. Validity was demonstrated by comparing changes on the measure across diagnoses, severity, and age groups. RESULTS: Several a priori hypotheses were supported; however, relationships with parent and therapist ratings were not clearly demonstrated. CONCLUSION AND DISCUSSION: The measure was found to be differentially responsive to changes in "stable" and "responsive" groups.

Analysis of Variance↗
PubMed1994

Training users in the gross motor function measure: methodological and practical issues.

BACKGROUND AND PURPOSE: The Gross Motor Function Measure (GMFM) is a criterion-referenced observational measure for assessing change in gross motor function for children with cerebral palsy (CP). The purposes of this report are to present data on the effects of training pediatric developmental therapists to administer and score the GMFM and to discuss some practical and methodological issues associated with training. SUBJECTS AND METHODS: A weighted kappa estimate pretraining and posttraining workshop was used to determine participants' agreement of scoring a videotaped GMFM assessment against experts' scoring of the same videotaped assessment. Several children with CP, representing a spectrum of ages, severities, and levels of function, were shown on the videotape. RESULTS: There was a significant improvement in agreement from a mean kappa of .58 to .82 (t = 15.38, df = 75, P < .001) for the first group and from .81 to .92 (t = 10.91, df = 72, P < .001) for the second group following training. CONCLUSION AND DISCUSSION: Although there are a number of advantages to using videotapes to train test users and to assess scoring reliability, this method does not evaluate participants' ability to administer the measure. Further work is needed to determine whether reliability is maintained in a clinical situation in which it is necessary to both administer and score the GMFM.

Adolescent↗
PubMed1993

Fiber gene and genomic origin of human adenovirus type 4.

The origin of human adenovirus type 4 (Ad4), an important pathogen and candidate vaccine vector, has been the subject of speculation. Ad4 is unusual among adenoviruses, because it is the single known serotype of subgroup E. Some biological and biochemical properties of Ad4 resemble those of serotypes from subgroups B and C. The length of Ad4 fiber is intermediate between that of subgroup B and C fibers. We sequenced the Ad4 fiber gene, locus of the determinant(s) of adenovirus serotype. The number of repeating DNA sequence motifs in the shaft domain of the Ad4 fiber gene is consistent with its reported length. Regional phylogenetic analysis of Ad4 was undertaken, comparing DNA sequences of early genes and fiber genes from representative adenoviruses. The Ad4 fiber gene has close phylogenetic relationship to subgroup C fiber genes. This is in distinct contrast to the closer relationship of Ad4 to subgroup B adenoviruses in early gene sequences, distributed across the left 70% of the viral genome. We propose that Ad4 originated by recombination of genomes resembling contemporary subgroup B and subgroup C adenoviruses. This event may have occurred so recently that divergence of subgroup E serological determinants has yet to be observed.

Adenovirus Early Proteins↗
PubMed1992

Proton NMR assignments of systemin.

Complete proton NMR assignments have been made for a synthetic 18-amino acid peptide named systemin, which functions as a wound-induced polypeptide hormone in tomato plants, and three of its derivatives. The wild-type peptide and this synthetic homolog have equivalent activities in their functional roles as systemic inducing signals in tomato plants. Proton NMR studies were carried out to characterize the solution properties of systemin. A variety of homonuclear proton NMR experiments at both 500 and 600 MHz were utilized in making these assignments, which have resulted in additional structural information. Whereas these results provide no evidence for persistence of common secondary (helix, sheet) or tertiary structural elements in the systemin polypeptide, there is evidence for two distinct molecular conformations at the carboxy terminus.

Amino Acid Sequence↗
PubMed1991

Proton homonuclear correlated spectroscopy as an assignment tool for hyperfine-shifted resonances in medium-sized paramagnetic proteins: cyanide-ligated yeast cytochrome c peroxidase as an example.

Two types of homonuclear proton COSY experiments are shown to be useful in making resonance assignments in cyanide-ligated cytochrome c peroxidase, a 34 kDa paramagnetic heme protein. Both magnitude COSY and phase-sensitive COSY experiments provide spectra useful for making proton assignments to resonances of strongly relaxed hyperfine-shifted protons. This initial investigation demonstrates that COSY experiments combined with NOESY experiments are feasible for hyperfine-shifted protons of paramagnetic proteins larger than metmyoglobins and ferricytochromes c, for which the nuclear spin-lattice relaxation times are in the range 70-300 ms. Taken together, COSY and NOESY experiments, although not yet widely applied to paramagnetic metalloproteins, provide a reliable protocol for accurately assigning hyperfine-shifted resonances that are part of a metalloenzyme's active site. Specific examples of expected proton homonuclear COSY connectivities that were not observed in these experiments are presented, and utilization of COSY with respect to the proton resonance line widths and apparent nuclear relaxation times is discussed. The COSY experiments presented here provide valuable verification of previously proposed hyperfine resonance assignments for cyanide-ligated cytochrome c peroxidase, which were made by using NOESY experiments alone, and in several instances expand these assignments to additional protons in particular amino acid spin systems.

Cyanides↗
PubMed1991

Measuring quality of movement in cerebral palsy: a review of instruments.

There is a lack of appropriate evaluation instruments in the area of quality of movement in cerebral palsy. Ten measures of quality of movement, or gross motor performance, published between 1965 and 1990, were reviewed according to established criteria. These criteria include the purpose of the measure, validity, reliability, responsiveness, range of items, and description of qualitative components. These measures provide a foundation for further instrument development in the area of quality of movement. [Boyce WF, Gowland C, Rosenbaum PL, et al. Measuring quality of movement in cerebral palsy: a review of instruments.

Cerebral Palsy↗
PubMed1991

Development of a quality-of-movement measure for children with cerebral palsy.

Development of a suitable measure of quality of movement, or gross motor performance, for children with cerebral palsy is a complex undertaking. A variety of conceptual, methodological, and practical issues inherent in such a project are discussed in this article. We report on the methodology used in the planning and construction of the Gross Motor Performance Measure. The measure has been developed by a multicenter, interdisciplinary group of therapists, methodologists, research staff, and international experts. Five attributes of gross motor performance have been defined, scaled, and operationalized. Results of content validity studies demonstrate that the measure has adequate completeness, clarity, and potential for evaluating change in quality of movement in children who have cerebral palsy. The measure is currently undergoing extensive testing to determine the reliability, validity, and responsiveness of the obtained scores. [Boyce WF, Gowland C, Hardy S, et al. Development of a quality-of-movement measure for children with cerebral palsy.

Cerebral Palsy↗
PubMed1990

Issues in measuring change in motor function in children with cerebral palsy: a special communication.

Assessing clinical change in motor function in children with cerebral palsy is a complex measurement task. Whereas a variety of methods have been developed to quantify specific aspects of gross motor behavior (eg, gait analysis, electrophysiological tests, energy-consumption techniques), systematic measurement of overall gross motor function is a more difficult problem. This special communication reviews the structural and performance characteristics required of a well-developed, valid, and responsive clinically based evaluative measure. We discuss several recent approaches used to assess responsiveness and critically examine clinical measures used in randomized controlled trials of physical therapy for children with cerebral palsy. It is argued that the creation and validation of responsive evaluative measures is essential if we are to assess accurately whether our treatments do more good than harm.

Cerebral Palsy↗
PubMed1989

The gross motor function measure: a means to evaluate the effects of physical therapy.

This paper reports the results of a study to validate a measure of gross motor function in detecting change in the motor function of disabled children. Physiotherapists used this instrument to assess 111 patients with cerebral palsy, 25 with head injury and 34 non-disabled preschool children on two occasions, the second after an interval of four to six months. Parents and therapists independently rated the children's function within two weeks of each assessment, and a sample of paired assessments was videotaped for 'blind' evaluation by therapists. Correlations between scores for change on this measure and the judgments of change by parents, therapists and 'blind' evaluators supported the hypothesis that the instrument would be responsive to both negative and positive changes.

Adolescent↗
PubMed1985

Coenzyme A biosynthesis: steric course of 4'-phosphopantothenoyl-L-cysteine decarboxylase.

4'-Phosphopantothenoyl-L-cysteine decarboxylase (PPC decarboxylase) was partially purified from rat liver. 4'-Phosphopantothenoyl[2-2H1]-L-cysteine was synthesized and converted by PPC decarboxylase to 4'-phosphol[1-2H1]pantetheine. The product was degraded by reduction with Raney nickel followed by acidic hydrolysis to [1-2H1]ethylamine. The latter was converted to the (-)-camphanamide derivative, NMR studies of which revealed that the deuterium was located in the pro-1S position. Also, unlabeled 4'-phosphopantothenoyl-L-cysteine was incubated with PPC decarboxylase in D2O, giving, after degradation, the (-)-camphanamide of (1R)-[1-2H1]ethylamine. The results show that the decarboxylation takes place with retention of configuration. These results are discussed in terms of possible mechanisms for the decarboxylation.

Animals↗