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Biomedical subjects

D Elliott

Publications and source records attributed to D Elliott.

At least 109 records · Page 6Linked to original sources
PubMed1993

Cerebral specialization for speech perception and movement organization in adults with Down's syndrome.

Adults with Down's syndrome and a group of undifferentiated mentally handicapped persons were examined using a free recall dichotic listening procedure to determine a laterality index for the perception of speech sounds. Subjects also performed both the visual and verbal portions of a standard apraxia battery. As in previous research, subjects with Down's syndrome tended to display a left ear advantage on the dichotic listening test. As well, they performed better on the apraxia battery when movements were cued visually rather than verbally. This verbal-motor disadvantage increased as the left ear dichotic listening advantage became more pronounced. It is argued that the verbal-motor difficulties experienced by persons with Down's syndrome stem from a dissociation of the functional systems responsible for speech perception and movement organization (Elliott and Weeks, 1990).

Aged↗
PubMed1993

Asymmetries in the regulation of visually guided aiming.

An experiment was conducted to examine the contribution of sensory information to asymmetries in manual aiming. Movements were performed in four vision conditions. In the full-vision condition (FV), subjects were afforded vision of both the hand and the target throughout the course of the movement. In the ambient-illumination-off condition (AO), the room lights were extinguished at movement initiation, preventing vision of the moving limb. In the target-off (TO) condition, the target was extinguished upon initiation of the movement. In a no-vision (NV) condition, ambient illumination was removed and the target was extinguished upon initiation of the response movement. Results indicated that accuracy was superior in the full-vision and target-off conditions and when movements were made by the right hand. Movements made by the right hand were also of shorter mean duration. The magnitudes of performance asymmetries were uninfluenced by vision condition. Analyses of movement kinematics revealed that movements made in conditions in which there was vision of the limb exhibited a greater number of discrete modifications of the movement trajectory. On an individual-trial basis, no relationship existed between accuracy and the occurrence of discrete modifications. These data suggest that although vision greatly enhances accuracy, discrete modifications subserved by vision reflect the imposition of nonfunctional zero-order control processes upon continuous higher-order control regimes.

Journal Article↗
PubMed1993

Variance and invariance in expert and novice triple jumpers.

The purpose of this study was to examine relative timing, relative distance, and effector independence characteristics of the triple jump. We videotaped expert and novice triple jumpers using standing and running starts. On some trials, the triple jumpers were required to take off from their nondominant leg. Gentner's (1987) interaction test was used to assess the proportional duration model in describing the timing of the component submovements. For both experts and novices, the proportional durations varied with the type of start. For experts, the relative timing of the jump components was independent of the take-off leg. The findings were mixed for the novices. Similar results were obtained when relative distance was examined. These results are discussed with respect to constructs related to variability in skilled performance.

Adult↗
PubMed1993

Movement preparation in adults with and without Down syndrome.

This study was designed to determine whether adults with mental retardation, with and without Down syndrome, display flexibility in the preparation of limb movements. A four-alternative target-aiming task involving movements with either the right or left hand to near or far targets was employed. Prior information about the movement to be made was manipulated by precuing specific features. Although reaction times and movement times were longer for subjects with than for those without mental retardation, the pattern of results was similar. Specifically, both retarded groups were able to use advance information to reduce movement preparation time. Moreover, information about movement distance was useful to subjects whether or not hand was precued. This finding indicates that the individuals with mental retardation were not limited by a fixed-order movement preparation process.

Adult↗
PubMed1992

Granuloma T lymphocytes in murine schistosomiasis mansoni have somatostatin receptors and respond to somatostatin with decreased IFN-gamma secretion.

The granulomas of mice infected with Schistosoma mansoni for 8 wk have macrophages that secrete somatostatin 1-14 (SOM). Within the granuloma, SOM has no known function. To uncover the possible significance of SOM produced within this granulomatous inflammation, we sought SOM receptors on distinct cellular components of the granuloma to identify cells targeted for SOM action. [125I]SOM 1-14 bound to dispersed granuloma inflammatory cells specifically and reversibly. Scatchard analysis suggested one receptor type (kDa 4.28 x 10(-9) M). Octreotide, a stable SOM derivative, displaced radioligand (kDa 1.01 x 10(-10) M), but SOM 1-28, substance P, and vasoactive intestinal peptide did not. The SOM receptor localized exclusively to a subset of granuloma CD4+ T lymphocytes. Using IL-5 and IFN-gamma ELISA, it was shown that granuloma T cells can secrete appreciable IL-5 and IFN-gamma when stimulated with Ag or mitogen. Both SOM and octreotide at concentrations as low as 10(-10) M substantially decreased IFN-gamma secretion from Ag or mitogen-stimulated T cells, but at concentrations as high as 10(-6) did not affect IL-5 production. Octreotide administered to animals in vivo decreased the intensity of the granulomatous response. Thus, some granuloma T cells have SOM 1-14 receptors. SOM 1-14, a product of granuloma macrophages, may participate in regulation of the granulomatous response by modulating the secretion of some lymphokines. Octreotide, a clinically useful SOM analog, mimics the action of SOM on the immune system.

Animals↗
PubMed1992

The use of power tools in the insertion of cortical bone screws.

Cortical bone screws are commonly used in fracture surgery, most patterns are non-self-tapping and require a thread to be pre-cut. This is traditionally performed using hand tools rather than their powered counterparts. Reasons given usually imply that power tools are more dangerous and cut a less precise thread, but there is no evidence to support this supposition. A series of experiments has been performed which show that the thread pattern cut with either method is identical and that over-penetration with the powered tap is easy to control. The conclusion reached is that both methods produce consistently reliable results but use of power tools is much faster.

Bone Screws↗
PubMed1992

Asymmetries in the spatial localization of transformed targets.

This study was designed to examine the contribution of the right cerebral hemisphere in the spatial localization of visual targets for manual aiming. Visual targets were briefly presented to the right and left fields and subjects were required to point either to the target location, or a "mirror" image of the target location with their right or left index finger. Whereas reaction times were faster for left-hand pointing than for right-hand pointing, there was no differential effect of the mirror image transformation. This suggests that left-hand reaction time advantages are more related to right hemisphere involvement in the spatial parameterization of the movement than spatial localization of the target.

Adult↗
PubMed1992

Asymmetries in the discrete and pseudocontinuous regulation of visually guided reaching.

An experiment was conducted to examine the contribution of the hemispheres to the organization of aiming movements. The spatial positions of targets were obtained by extrapolating from brief visual displays of geometric patterns. The patterns comprised linear, quadratic, cubic, and quartic mathematical functions and varied in spatial complexity. Vision of the hand was also manipulated. While the hands did not differ in spatial accuracy, movements made by the right hand were of shorter duration and had higher peak velocities. The stimulus pattern strongly influenced kinematics, in particular the number of discrete modifications of the movement trajectory. Vision of the hand resulted in superior accuracy, although subjects were unable to compare the relative positions of the limb and the target. Vision of the hand did not lead to an increase in discrete adjustments, suggesting that visual information was used in a continuous fashion. Movements into ipsilateral space differed from those into contralateral space with respect to a number of parameters.

Adult↗
PubMed1992

Measuring patient anxiety in coronary care. Part 1.

Patient anxiety is a common problem identified by nurses. However, the difficulty of assessing the level and significance of the anxiety is problematic. This paper discusses the issue of measuring patient anxiety, specifically in Coronary Care. As well as discussing physiological measures, three appropriate psychometric instruments are identified (the State-Trait Anxiety Inventory--STAI; the Hospital Anxiety and Depression Scale--HAD; a Linear Analogue Anxiety Scale--LAAS), along with a review of the relevant literature. Systematic anxiety measurement, and management of maladaptive anxiety would appear to be appropriate and meaningful nursing functions within the provision of holistic patient care in Coronary Care.

Anxiety Disorders↗
PubMed1992

A review of nursing strategies to reduce patient anxiety in coronary care. Part 2.

Illness and associated hospitalisation are stressful events for any individual. The stress associated with an admission to a coronary care unit may be related to the severity and acuteness of the illness, the effects of hospitalisation on the individual, their family, their job and financial position, and often manifests itself as anxiety, fear or depression. This paper highlights the use of anxiety reduction strategies such as muscle relaxation, music, education and counseling. The literature reviewed does not provide any clear messages regarding the effectiveness of these strategies in the coronary care unit setting. As a consequence, there is a need to continue researching this important area of nursing practice.

Coronary Care Units↗
PubMed1992

Renal transplant artery rupture secondary to candida infection.

We report a case of a diabetic renal transplant patient with candiduria who developed repeated elevations in serum creatinine concentration due to an intermittently obstructing candida ball in the urinary tract. After unsuccessful attempts to place a nephrostomy tube for local irrigation and debulking, the renal graft artery ruptured secondary to extensive perirenal candida infection. Percutaneous nephrostomy may increase the risks of renal and extrarenal tissue infection with the potential for fatal complications such as infection of the vascular anastomosis.

Adult↗
PubMed1992

Anabolic steroid use among adolescents in a rural state.

BACKGROUND: Anabolic-androgenic steroid use is an increasing problem among high school students. Previous reports have been mainly from metropolitan areas. METHODS: We report the first study of anabolic-androgenic steroid use to concentrate on rural communities. The study was conducted using an anonymous survey of a random sample of male high school students (N = 3900) in grades 10 through 12 encompassing 31 high schools in a predominantly rural state. RESULTS: Two-hundred five (5.3%) students reported using steroids. The prevalence of illicit drug use was significantly higher (P < .05) in steroid users (74%) than in nonusers (31%) (P < .001). The association was between anabolic-androgenic steroid use and illicit drug use rather than between sports participation of any type and illicit drug use (P > .2). Comparison of the prevalence of illicit drug use among athletic (63.2%) and nonathletic (36.8%) steroid users found no significant difference. Findings were similar with cigarette use. There was no difference in the rate of steroid use by school enrollment (69 to 1495) or by city population size (< 200 to 64,000). The predominant reason for steroid use was to improve appearance (43%). CONCLUSIONS: This study found the prevalence of steroid use throughout a predominantly rural state to be similar to that found by previous studies conducted in metropolitan areas; prevalence was not affected by city or school size. Steroid use was closely associated with illicit drug and cigarette use, a new finding that deserves further examination.

Adolescent↗
PubMed1992

A dose-finding study with remoxipride in the acute treatment of schizophrenic patients.

Two hundred and forty-two patients with acute schizophrenia were enrolled in a double-blind, comparative, dose-finding study of a novel antipsychotic, remoxipride. Remoxipride was evaluated in a low (30 to 90 mg), medium (120 to 240 mg) and a high (300 to 600 mg) dose range and compared with a haloperidol (15 to 45 mg), which was administered to a similar group of patients. The results support the antipsychotic effect of remoxipride, with maximum efficacy occurring at daily doses between 120 mg and 600 mg. Side-effects were more frequent at doses of remoxipride over 300 mg. In all groups, remoxipride caused consistently fewer extrapyramidal side-effects than haloperidol. The antipsychotic effect of remoxipride may be derived from specific blockade of dopamine D2 receptors in the mesolimbic tract. The findings also suggest that remoxipride may have a therapeutic effect on negative symptoms of schizophrenia.

Dose-Response Relationship, Drug↗
PubMed1991

Angiographic assessment of arterial outflow: predictive value of a new classification system.

A prospective study with 4 years of follow-up involving 127 consecutive symptomatic patients (60.6% with claudication, 39.4% with critical ischemia) who underwent aortobifemoral bypass surgery is described. A new grading system for the classification of arterial outflow was applied to determine its usefulness in predicting the outcome of surgery. Preoperative angiograms were numerically scored according to the arterial outflow status at the level of main segmental involvement. Higher scores corresponded to worse outflows. Outflow scores ranged between 1 and 10 with a mean of 3.6 +/- 0.24. The main comparison was between patients with scores of less than 5 (group A, n = 80) and patients with scores of 5 or more (group B, n = 47). Better outflow was associated with higher postoperative mean increases in the ankle-brachial index (ABI) (group A, 0.35 +/- 0.03; group B, 0.17 +/- 0.04; P less than .001) and transcutaneous oximetry (PtcO2) (group A, 15.4 mm Hg +/- 1.8; group B, 8.4 mm Hg +/- 3.0; P = .01). At 4-year follow-up, group A had higher cumulative rates of patency (98.3% vs 78.0%, P less than .001), symptomatic relief (84.0% vs 23.3%, P less than .001), and palliation (67.0% vs 19.9%, P less than .001). In conclusion, angiographic outflow, as evaluated with the system described, successfully helped predict postoperative increases in ABI and PtcO2 and the cumulative rates of graft patency, symptomatic relief, and palliation.

Angiography↗
PubMed1991

Open subtalar dislocation.

Open subtalar dislocation is a rare injury, accounting for about 0.1% of all dislocations and, consequently, the natural history and outcome of this injury and their relevance to treatment are not well documented. A retrospective study at Westmead Hospital revealed 10 patients who presented with this injury between 1978 and 1988. We had the opportunity to review all of these patients in 1987 and again in 1989. We found a high incidence (60%) of poor results, and that the only factor that influenced the outcome was infection. It is concluded that the poor prognosis is due to the nature of the injury itself, rather than any particular factors in the subsequent management. Specifically, there was no relation to the direction of the dislocation, the presence of fractures in the foot, the time elapsed before reduction, or the period of immobilization.

Adult↗