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R Elliott

Publications and source records attributed to R Elliott.

At least 37 records · Page 2Linked to original sources
PubMed1997

Examination-induced distress in a public examination at the completion of secondary schooling.

BACKGROUND: The context for this study was the Higher School Certificate examination in New South Wales, Australia. AIMS: The main research aim was to investigate the association between the Higher School Certificate, the reported distress and anxiety levels of the adolescent students who prepare for and sit for the examination, and various other internal and environmental variables. SAMPLE: The random sample consisted of 445 students in their last two years of secondary schooling, with approximately equal numbers of males and females from a diverse range of ethnic backgrounds. METHODS: Analysis was carried out using principal components analysis and multiple regression. RESULTS: The most significant contribution to distress associated with the examination was made by the personality trait, anxiety proneness. Lower socio-economic status, self-confidence, academic and verbal self-concepts and perceived ability to cope were also found, to a lesser extent, to be associated with increased distress. The interactions sex with ethnic background and year with ethnic background were of particular interest. Students who were male and had an English speaking background, and students in year 11 who had an English speaking background were least likely to experience distress than others in the context of the examination. CONCLUSIONS: Whilst results must be treated with caution, particular groups of students potentially vulnerable to distress were identified and directions for future research indicated.

Adolescent↗
PubMed1997

Abnormal response to negative feedback in unipolar depression: evidence for a diagnosis specific impairment.

OBJECTIVES: To assess in further detail the specific form of motivational impairment influencing neuropsychological performance in depression-oversensitivity to perceived failure. The present study considers two questions: firstly whether this is specific to depression and secondly how the effect relates to clinical features. METHODS: Unipolar depressed patients and matched controls were assessed on two neuropsychological tests giving explicit performance feedback. The data were analysed in two separate studies to consider the questions above. The first study considered the specificity of the effect to depressed patients, using data on the same tests collected from other patient groups. The second study was a longitudinal assessment of the depressed patients on clinical recovery to determine whether the effect is specific to the depressed state. RESULTS: The effect was not seen in non-depressed patient groups, either neurological or psychiatric groups. The longitudinal study showed a residual abnormal response to negative feedback on clinical recovery. CONCLUSIONS: Abnormal response to negative feedback is specific to a primary diagnosis of depression and may be a trait rather than a state factor of the disorder. These results are discussed in relation to the putative neuropathology of depression and also to cognitive and behavioural accounts of the disorder. The findings presented here have important implications for establishing a link between mood and cognition in unipolar depression.

Adult↗
PubMed1996

Lack of autoimmune serological reactions in rodent models of insulin dependent diabetes mellitus.

Spontaneous insulitis with insulin-dependent diabetes mellitus (IDDM) in rodent models, the BB rat and NOD mouse, has clarified the pathogenesis of and guided decisions on interventional therapy for human IDDM. However, the occurrence in such models of a standard marker of human IDDM, autoantibodies to beta islet cell constituents, has been controversial. Hence we assessed diabetes-prone rodents for the frequencies of raised levels of auto-antibodies to glutamic acid decarboxylase GAD (anti-GAD), insulin and heat shock protein 65 (HSP-65) in relation to levels in non-diabetes-prone animals and levels in human diabetic sera. Assays were performed sequentially at various ages of life. The immunoassays used for anti-GAD and anti-insulin were those validated for sensitivity and specificity for detection of the corresponding autoantibodies in human IDDM sera at international workshops. Positive controls included human IDDM sera with reactivity with GAD or insulin and, for mouse anti-GAD, the highly reactive monoclonal antibody, GAD-6. The results were that levels of autoantibodies in diabetes-prone BB rats or NOD mice to the "IDDM-relevant' autoantigens in our panel did not exceed levels in control rats or mice, and were much lower than levels in humans with IDDM. We conclude that the BB rat and NOD mouse represent a model, but not a facsimile, of human IDDM and that therapeutic successes in such models should be interpreted with caution in relation to interventional therapy for human IDDM.

Animals↗
PubMed1996

Molecular epidemiology of IDDM in the Western Pacific Rim Region. WHO DiaMond Molecular Epidemiology Sub-Project Group.

HLA-DQA11 and DQB1 alleles coding for arginine (R) in position 52, and an amino acid other than aspartic acid (ND) in position 57, respectively, are strong genetic markers for IDDM in Caucasians. However, their contribution to the occurrence of the disease in Asian populations is less clear. As part of the WHO DiaMond Molecular Epidemiology Sub-Project, HLA-DQ molecular typing was performed for IDDM cases and non-diabetic controls from three populations in the Western Pacific Rim Region where incidence rates have been established (Hokkaido, Japan; Seoul, Korea; Auckland, New Zealand). DQA1*R homozygosity was significantly associated with IDDM in all areas. DQB1*ND homozygosity was also related to IDDM in Korea and New Zealand, but not in Japan. Individuals who were homozygous for DQA1*R and DQB1*ND were at highest IDDM risk in Korea and New Zealand, with the most striking findings in Auckland. In Japan, individuals carrying two DQA1*R, but only one DQB1*ND allele, were most likely to develop IDDM. These data revealed considerable genetic heterogeneity between Japan and Korea and suggest that DQA1*R and DQB1*ND alleles may explain a larger proportion of IDDM incidence in Caucasian compared to Asian populations.

Alleles↗
PubMed1996

Neuropsychological impairments in unipolar depression: the influence of perceived failure on subsequent performance.

The CANTAB battery of neuropsychological tests was used to compare the performance of 28 patients with unipolar depression with that of 22 age and IQ matched controls. The patients were impaired on almost all tests studied with deficits in pattern and spatial recognition memory, matching to sample, spatial span, spatial working memory and planning. Most of the patients showed at least some impairment and deficits were seen across cognitive domains. An important finding was the detrimental effect of failure on subsequent performance; having solved one problem incorrectly, patients were far more likely than controls to fail the subsequent problem. Superimposed on the general deficits, there were also specific deficits in executive tasks characteristic of frontostriatal dysfunction and deficits in mnemonic tasks characteristic of temporal lobe dysfunction. This combination of a specific form of motivational deficit, resulting in oversensitivity to negative feedback, and superimposed specific neuropsychological deficits were correlated with severity of depression. The most significant correlations were seen between mnemonic deficits and clinical rating scores. Comparisons of the deficits seen in the depressed patients in this study with other patient groups assessed with the CANTAB neuropsychological battery, showed that one of the hypotheses of the neuropsychological deficits in depression, that of "frontosubcortical' or "frontostriatal' dysfunction, was not supported. These findings are discussed in relation to the likely neural substrates of depression.

Adult↗
PubMed1996

Neuropsychology--dementia and affective disorders.

The neuropsychology of dementia and depression is surveyed with a focus on dementia of Alzheimer type (DAT) and depression in old age. Some of the main cognitive deficits in DAT are identified as loss of memory for events and attentional or executive deficit. The course of deterioration across various cognitive domains in DAT is consistent with a posterior-to-anterior spread of pathology in the cerebral cortex. Depressed, elderly patients exhibit a generalised profile of deficits, with impairments in tests shown to be sensitive to temporal or frontal cortex dysfunction. The depressed also exhibit a specific deficit in response to negative feedback (failure) which may contribute to different forms of cognitive dysfunctioning. Gross similarities in the deficits presented by subjects in depression or DAT necessitate a search for qualitative differences between the two, in order to facilitate their differential diagnosis: one such difference is the reversibility of certain of the cognitive deficits following recovery from depression.

Brain↗
PubMed1996

Multivariate allometric scaling of men's world indoor rowing championship performance.

The World Indoor Rowing Championship (WIRC) is based on the time (T) to row a simulated 2500 m on a rowing ergometer. In the WIRC there are separate age categories but only two weight classes: light and heavyweight, thus penalizing those just heavier and those significantly lighter than the cut-off weight. Multivariate allometric scaling (MAS) provides an expression of performance free of the confounding effect of more than one scaling variable. We used MAS to scale T by height (H) and age (A) to create a new index of rowing performance, T*H(-a)*A(-b). Subjects were 148 male competitors from the 1995 WIRC. MAS indicated that T*H*A(-0.06) expresses T free of the confounding effect of H and A. We also scaled T only by H on those subjects, A < 40, (N = 109). Results showed that T*H is an optimal and particularly feasible scaling of T. Use of either convention dramatically changed race results. In conclusion, we recommend use of either the T.H (17 < or = A < or = 39) or T*H*A(-0.06) conventions to adjust WIRC performance in adult males.

Age Factors↗
PubMed1996

Future shock?

Explore the source record for details and available documents.

Animals↗
PubMed1995

Neuropsychological deficits in tests of executive function in asymptomatic and symptomatic HIV-1 seropositive men.

There has been much debate about the exact nature and time of onset of the cognitive impairments associated with infection by the human immunodeficiency virus type 1 (HIV-1). Studies to date have not reached consistent conclusions. The present study comprised 22 asymptomatic and 18 symptomatic HIV-1 seropositive men, whose only risk factor for contraction of the virus was sexual intercourse, and 18 seronegative controls matched for age and IQ. Subjects were given computerized neuropsychological tests from the CANTAB battery, which assessed visuospatial memory, attention and executive function. Both the asymptomatic and the symptomatic HIV-1 seropositive subjects showed a selective pattern of deficits relative to the controls. In addition, the seropositive subjects were subtly but significantly impaired on tests of executive function but unimpaired on certain tests of visual memory. This finding supports an hypothesis that frontostriatal dysfunction occurs in HIV-1 infected individuals prior even to the expression of clinical symptoms.

Adult↗
PubMed1995

Neuropsychological evidence for frontostriatal dysfunction in schizophrenia.

Schizophrenics and controls were compared on a computerized test of attentional set-shifting which provides a componential analysis of the Wisconsin Card Sort Test and has previously been shown to be sensitive to frontal lobe dysfunction and Parkinson's disease. The main test was of extra-dimensional shifting where subjects are required to shift response to an alternative perceptual dimension. In one condition, termed 'perseveration', subjects are required to shift to a novel dimension and ignore the previously relevant one. In the other condition, termed 'learned irrelevance', subjects are required to shift to the previously irrelevant dimension and ignore a novel one. Chronic medicated schizophrenics (N = 32) show a highly significant impairment on the perseveration but not the learned irrelevance condition, as compared to normal age and IQ matched controls (N = 24). This was true even of a subgroup of patients with preserved IQ. The impairments in attentional set-shifting failed to correlate with patients' scores on the Mini-Mental State Examination (mean; S.D. 26.8; 1.8) or with scores on a test of recognition memory. These results provide evidence for a specific deficit in a set-shifting test of executive function and support a hypothesis of frontostriatal dysfunction in schizophrenia.

Adult↗
PubMed1995

Control of coccidia in young calves using lasalocid.

Thirty-six, 2- to 4-day-old Friesian bull calves were divided into 4 groups and fed milk replacer and calf starter pellets ad libitum in separate pens. Four treatments were applied; lasalocid in milk (1 mg/kg body weight/day) (M), lasalocid in starter (F), lasalocid in both milk and starter (M + F) and untreated (C). When the calves were about 2 weeks old they were each dosed orally with 550,000 sporulated Eimeria sp oocysts, mainly E zurneii and E bovis. The infection, detected by faecal excretion of oocysts, was suppressed in the M + F and M groups. There was significant excretion of oocysts in the F group but these calves did not show any clinical signs of coccidiosis. Untreated calves were affected with diarrhoea containing blood on the 24th day after inoculation. Body weight gain and intake of starter pellets was also depressed in the untreated calves during the time they were clinically affected. It is concluded that mixing lasalocid in milk replacer (or fresh milk) is an effective method of protecting young calves against early infection with coccidia.

Animals↗
PubMed1995

Altered glucose dependence of glucagon-like peptide I(7-36)-induced insulin secretion from the Zucker (fa/fa) rat pancreas.

In previous studies on the enteroinsular axis in Zucker rats, it was found that glucose-dependent insulinotropic polypeptide (GIP) levels were normal in obese animals, but the glucose threshold for the insulinotropic action of GIP in the perfused rat pancreas was reduced. Glucagon-like peptide I (GLP-I)(7-36) is also an important incretin, and in the current study, glucose, insulin, and immunoreactive (IR)-COOH-terminal GLP-I responses to oral glucose were compared in lean (Fa/?) and obese (fa/fa) rats. In addition, the concentration thresholds for stimulation and glucose dependence of perfused pancreases to GLP-I(7-36) were examined. Glucose responses to oral glucose were similar in fa/fa and Fa/? rats. Obese animals were hyperinsulinemic when fasting and after oral glucose. Significant increases in IR-GLP-I levels in response to glucose were only observed in fa/fa rats. Perfused pancreases from fa/fa rats hypersecreted insulin at all glucose concentrations. In the presence of 4.4 mmol/l glucose, GLP-I(7-36) increased insulin secretion in fa/fa pancreases approximately 25-fold, whereas there was only a 5-fold increase in Fa/? pancreases. Pancreases from fa/fa rats, perfused with a glucose gradient (2.8-11 mmol/l) in the presence of GLP-I(7-36), responded with an immediate increase in insulin secretion, i.e., at a glucose concentration of 2.8 mmol/l, whereas Fa/? pancreases required a minimum of 4.22 mmol/l glucose for stimulation. With high glucose (16.7 mmol/l), both fa/fa and Fa/? rat pancreases exhibited similar responsiveness to GLP-I(7-36), having thresholds of < 50 pmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Loss of heterozygosity in spontaneous and chemically induced tumors of the B6C3F1 mouse.

The B6C3F1 mouse is used worldwide to gauge the carcinogenic hazard posed by chemicals to humans. An assessment of the ability of this rodent model to predict human neoplasia requires an evaluation of similarities and differences in the genetics of tumor formation between these two species. We examined 142 spontaneous and chemically-induced liver tumors isolated from the B6C3F1 mouse for losses of heterozygosity (LOH) at 78 polymorphic loci and compared these results to genetic changes known to occur in human hepatocellular carcinoma. Approximately a third of the 142 mouse tumors exhibited LOH, suggesting that tumor suppressor gene inactivation may be involved in the formation of mouse liver tumors. Most of the LOH observed was restricted to seven chromosome sites and most of the tumors that underwent LOH lost alleles from only one of those seven sites. The relatively few losses seen in these mouse tumors distinguished them from clinical stage human tumors in that, in the mouse tumors, interstitial deletions appeared more frequently than losses of whole chromosomes. Only four mouse tumors lost a whole chromosome. LOH occurred at loci of the mouse genome syntenic to areas of the human genome known to harbor the Wilms', retinoblastoma, APC, MCC and DCC tumor suppressor genes; these genes have never been associated with hepatocellular carcinomas. Losses observed on chromosomes 5 and 8 (syntenic to human chromosomes 4 and 16) suggest tumor suppressor genes that are common to hepatocellular carcinomas from both species, while losses on chromosome 9 suggest involvement of a previously unidentified tumor suppressor gene.

Animals↗
PubMed1994

Emergency nurses' moral evaluation of patients.

Introduction Judgments by nurses concerning patients' moral fitness and the appropriateness of their visits to the emergency department are made constantly. The treatment rendered to patients is affected by these judgments. This study explored which patient characteristics emergency nurses used to morally evaluate patients, determined reasons the nurses gave for this behavior, and identified some factors that contributed to the evaluative behavior. Methods An exploratory, descriptive study with a mailed questionnaire was conducted on nurses working in emergency departments in hospitals throughout Alberta. Results Eighty-three questionnaires were completed and returned, representing a response rate of 55%. A hierarchy emerged from the data, validating previous research. Nature of the illness and diagnosis, in addition to certain patient characteristics, were critical in determining emergency nurses' attitudes. Nurses appeared to be unaware that they were acting prejudicially. Discussion When patients are aware of being disliked by the nurses caring for them, nurse-patient communication and relationship are jeopardized. This may affect care and, ultimately, recovery. Recommendations included encouraging nurses to recognize the dynamics, consequences, and inherent dangers of labeling patients and to improve their understanding of patients identified as unfavorable.

Alberta↗
PubMed1993

HTLV-II infection in Florida Indians.

A significantly increased prevalence of antibodies to human T-cell leukemia virus (HTLV) has been described in several native American populations in the United States and Latin America. Initial virologic studies indicate that HTLV-II is the predominant virus responsible for this antibody pattern. We obtained blood samples from 106 Seminole Indians living on four reservations in Southern Florida. Seropositivity to HTLV-I/II was found in 14 (13.2%) of these individuals. Polymerase chain reaction (PCR) documented HTLV-II and the absence of HTLV-I in 7 of the 9 donors available for follow-up testing of white blood cells. Evaluation of various risk factors excluded blood transfusion or intravenous drug use as an important contributing factor to the HTLV-II seroprevalence rate. These studies support the hypothesis that HTLV-II is endemic in many native American tribes in the Western hemisphere.

Florida↗
PubMed1992

"If you love someone, you don't hurt them": a comprehensive process analysis of a weeping event in therapy.

Early theorists described physical diseases (e.g., asthma, ulcers) thought to be associated with the inhibition of weeping (e.g., Alexander 1950), and catharsis theories (Breuer and Freud 1895/1955; Koestler 1964) postulated that unexpressed emotion accumulated as in a tank, and then overflowed as tears when a threshold level was exceeded. From a more biological perspective, it has been suggested that stress produces toxic chemicals in the body that become concentrated in the lacrimal gland and are released through weeping, restoring homeostasis (Frey 1985). As a result of these theories, psychotherapists tend to believe weeping is healthy for clients and that it serves to decrease depression (Trezza et al. 1988). While laboratory studies have typically not supported these ideas (e.g., Labott and Martin 1987, 1988), no studies have been performed on weeping specifically in the context of psychotherapy.

Adult↗