Showing papers by "Flinders University published in 2004"

The Role of Social Comparison in the Effect of Magazine Advertisements on Women's Mood and Body Dissatisfaction

Abstract: This study aimed to investigate the role of social comparison processes in women's responses to images of thin-idealized female beauty. A sample of 126 women viewed magazine advertisements containing full-body, body part, or product images. Instructional set was also manipulated with three levels: control, appearance focus, and social comparison. Mood and body dissatisfaction were measured immediately before and after advertisement viewing, while state weight anxiety and the amount of appearance comparison engaged in were measured only after the advertisements. It was found that exposure to either body part or full body images led to increased negative mood and body dissatisfaction, while the amount of comparison processing was affected by both image type and instructional set. Importantly, regression analyses showed that the effects of image type on mood and body dissatisfaction were mediated by the amount of social comparison reported. It was concluded that the processing in which women engage ...

Lessons from the Genome Sequence of Neurospora crassa: Tracing the Path from Genomic Blueprint to Multicellular Organism

Abstract: We present an analysis of over 1,100 of the approximately 10,000 predicted proteins encoded by the genome sequence of the filamentous fungus Neurospora crassa. Seven major areas of Neurospora genomics and biology are covered. First, the basic features of the genome, including the automated assembly, gene calls, and global gene analyses are summarized. The second section covers components of the centromere and kinetochore complexes, chromatin assembly and modification, and transcription and translation initiation factors. The third area discusses genome defense mechanisms, including repeat induced point mutation, quelling and meiotic silencing, and DNA repair and recombination. In the fourth section, topics relevant to metabolism and transport include extracellular digestion; membrane transporters; aspects of carbon, sulfur, nitrogen, and lipid metabolism; the mitochondrion and energy metabolism; the proteasome; and protein glycosylation, secretion, and endocytosis. Environmental sensing is the focus of the fifth section with a treatment of two-component systems; GTP-binding proteins; mitogen-activated protein, p21-activated, and germinal center kinases; calcium signaling; protein phosphatases; photobiology; circadian rhythms; and heat shock and stress responses. The sixth area of analysis is growth and development; it encompasses cell wall synthesis, proteins important for hyphal polarity, cytoskeletal components, the cyclin/cyclin-dependent kinase machinery, macroconidiation, meiosis, and the sexual cycle. The seventh section covers topics relevant to animal and plant pathogenesis and human disease. The results demonstrate that a large proportion of Neurospora genes do not have homologues in the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe. The group of unshared genes includes potential new targets for antifungals as well as loci implicated in human and plant physiology and disease.

Organizational citizenship behaviours in relation to job status, job insecurity, organizational commitment and identification, job satisfaction and work values

Abstract: This study investigated organizational citizenship behaviours (OCBs) in a sample of 154 school teachers from Victoria, Australia, of whom 101 were in permanent employment and 53 on fixed-term contracts. Participants completed measures of OCBs, job insecurity, organizational commitment, organizational identification, job satisfaction and work values relating to influence, variety and skill utilization. Results showed that the contract teachers reported more job insecurity and more OCBs compared to the permanent teachers. OCBs were positively related to perceived job insecurity and negatively related to opportunities to satisfy influence and skillutilization work values for the contract teachers, and positively related to organizational commitment, organizational identification and to opportunities to satisfy variety and skill-utilization work values for the permanent teachers. Results were discussed in relation to the different functions that OCBs were assumed to serve for both groups of teachers and the possibility of conceptualizing OCBs using a motivational analysis that takes account of expectations and goal structures.

The role of body objectification in disordered eating and depressed mood

Abstract: Objectives: The study aimed to extend tests of objectification theory into the realm of depression. The theory's applicability to men was also investigated. Design: A cross-sectional study. Method: A sample of 115 men and 171 women completed questionnaire measures of self-objectification, depressed mood, disordered eating, as well as the proposed mediating variables of body shame, appearance anxiety, flow and awareness of internal states. Results: For women, it was found that depressed mood and disordered eating were both predicted by self-objectification and its corollary of habitual self-surveillance. Path analysis gave strong support to the mediational relationships of the theoretical model. With one major exception (the role of self-objectification), the pattern of relationships was similar for men. Conclusion: Objectification theory provides a useful framework for identifying predictors of depressed mood.

The Abbey pain scale: a 1-minute numerical indicator for people with end-stage dementia

Abstract: The need for a specialized clinical regimen for patients with dementia who require palliative care has only recently been recognized. Structured approaches to palliative care are not well developed. The recognition and treatment of pain is an important part of this management risk. However, pain is consistently underdiagnosed and undertreated in this population. A factor contributing to this has been a lack of appropriate tools to help recognize and document pain. This study sought to develop and validate an easy-to-use pain scale for use in residential aged care homes. The tool was developed with residents with end- or late-stage dementia who were unable to articulate their needs, identified by the registered nurses who knew them. Results showed that following pain-relief intervention the average pain score recorded using the scale fell by more than half. A paired Student's t-test showed the reduction to be highly significant (P<0.001). Validity and internal reliability, assessed by calculating Gamma and Cronbach's alpha, were found to be satisfactory. Qualitative evidence gathered from users of the scale indicated that it was considered a useful clinical device that could be completed within one minute. Further analysis of the use of the scale in clinical settings, testing of inter-rater reliability and examination of the limitations found in this study will commence early in 2004.

Thin ideals in music television: a source of social comparison and body dissatisfaction.

Abstract: Objective The study investigated the impact of thin idealized images of women as presented in music television, a popular form of entertainment for young people. Methods A sample of 84 women viewed a videotape containing either appearance music videos (which emphasized appearance and featured thin and attractive women) or nonappearance music videos. The instructional set was also manipulated to encourage or discourage social comparison. Results Viewing the appearance music videos featuring thin women led to increased social comparison and body dissatisfaction. Regression analyses showed that the effect of video condition on body dissatisfaction was mediated by the level of comparison processing. Discussion The study demonstrated that the content of television programming can have negative consequences for women's body image. In addition, it offered social comparison processing as both a theoretic mechanism and a practical target for intervention. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 35: 48–58, 2004.

Human udp-glucuronosyltransferases: isoform selectivity and kinetics of 4-methylumbelliferone and 1-naphthol glucuronidation, effects of organic solvents, and inhibition by diclofenac and probenecid

Abstract: The glucuronidation kinetics of the prototypic substrates 4-methylumbelliferone (4MU) and 1-naphthol (1NP) by human UDP-glucuronosyltransferases (UGT) 1A1, 1A3, 1A4, 1A6, 1A7, 1A8, 1A9, 1A10, 2B7, 2B15, and 2B17 were investigated. Where activity was demonstrated, inhibitory effects of diclofenac, probenecid, and the solvents acetone, acetonitrile, dimethyl sulfoxide, ethanol, and methanol were characterized. All isoforms except UGT1A4 glucuronidated 4MU, whereas all but UGT 1A4, 2B15, and 2B17 metabolized 1NP. However, kinetic models varied with substrate (for the same isoform) and from isoform to isoform (with the same substrate). Hyperbolic (Michaelis-Menten), substrate inhibition, and sigmoidal kinetics were variably observed for both 4MU and 1NP glucuronidation by the various UGTs. K(m) or S(50) (sigmoidal kinetics) and V(max) values varied 525- (8-4204 microM) and 1386-fold, respectively, for 4MU glucuronidation, and 1360- (1.3-1768 microM) and 37-fold, respectively, for 1NP glucuronidation. The use of a two-site model proved useful for those reactions exhibiting non-Michaelis-Menten glucuronidation kinetics. The organic solvents generally had a relatively minor effect on UGT isoform activity. UGT 2B15 and 2B17 were most susceptible to the presence of solvent, although solvent-selective inhibition was occasionally observed with other isoforms. Diclofenac and probenecid inhibited all isoforms, precluding the use of these compounds for the reaction phenotyping of xenobiotic glucuronidation pathways in human tissues. Diclofenac and probenecid K(i) values, determined for selected isoforms, ranged from 11 to 52 microM and 96 to 2452 microM, respectively. Overall, the results emphasize the need for the careful design and interpretation of kinetic and inhibition studies with human UGTs.

Fluidity in the self-concept: the shift from personal to social identity

Abstract: Dominant personality models of the self-concept (e.g. self-schema theory) conceive of the self as a relatively stable cognitive representation or schema. The self-schema controls how we process self-relevant information across a myriad of situations. Conversely, self-categorization theory argues that self-perception is highly variable and context-dependent. It was hypothesized in two studies (N=114 and 200) that the effect of personal self-schemas on information-processing would be eliminated when the context makes a conflicting higher-order identity salient. Results largely supported self-categorization theory. Across various dependent measures (trait endorsements, response latencies, and confidence in self-descriptions), participants generally responded in line with the salient identity, even if this pattern of responding directly contradicted their personal self-schema. Implications for dominant personality models of the self-concept are examined. Copyright © 2004 John Wiley & Sons, Ltd.

Alternative nad(p)h dehydrogenases of plant mitochondria

Abstract: Plant mitochondria have a highly branched electron transport chain that provides great flexibility for oxidation of cytosolic and matrix NAD(P)H. In addition to the universal electron transport chain found in many organisms, plants have alternative NAD(P)H dehydrogenases in the first part of the chain and a second oxidase, the alternative oxidase, in the latter part. The alternative activities are nonproton pumping and allow for NAD(P)H oxidation with varying levels of energy conservation. This provides a mechanism for plants to, for example, remove excess reducing power and balance the redox poise of the cell. This review presents our current understanding of the alternative NAD(P)H dehydrogenases present in plant mitochondria.

Working memory components of the Corsi blocks task

Abstract: A computerized version of the Corsi blocks task (Milner, 1971) was assessed for standard forward-recall order (Experiments 1 and 3) and for reversed-recall order (Experiments 2 and 3) either in a single-task or in a dual-task design combined with articulatory suppression, matrix-tapping, random-interval generation or fixed-interval generation as concurrent tasks during the encoding stage. Concurrent performance of the matrix-tapping task impaired memory performance for short as well as for longer block sequences. The random-interval generation task, which loads executive processes, impaired memory performance mainly at intermediate- and longer-sequence lengths, while fixed-interval generation, which is presumed to put no load on executive processing, did not show any effect. Articulatory suppression did not impair memory performance on forward-recall order, but it impaired memory for longer sequences in the backward-recall condition in Experimentt 2, but not in Experiment 3. The results are discussed within the context of the working-memory model of Baddeley and Hitch (1974).

Evidence that TRPM8 is an androgen-dependent Ca2+ channel required for the survival of prostate cancer cells

Abstract: The Ca(2+)-permeable channel TRPM8 is thought to play an important role in the pathophysiology of prostate cancer. We have investigated the intracellular location of TRPM8 and its role as a Ca(2+)-permeable channel in an androgen-responsive and an androgen-insensitive prostate cancer cell line. We report evidence from immunofluorescence experiments that in the androgen-responsive LNCaP cell line, the TRPM8 protein is expressed in the endoplasmic reticulum and plasma membrane, acts as a Ca(2+)-permeable channel (assessed using Fura-2 to measure increases in the cytoplasmic Ca(2+) concentration) in each of these membranes, and is regulated by androgen. Although TRPM8 was detected in the androgen-insensitive PC-3 cell line, no evidence was obtained for regulation of its expression by androgen. The results of experiments using LNCaP cells, the TRPM8 antagonist capsazepine, and small interference RNA targeted to TRPM8 indicate that TRPM8 is required for cell survival. These results indicate that TRPM8 is an important determinator of Ca(2+) homeostasis in prostate epithelial cells and may be a potential target for the action of drugs in the management of prostate cancer.

Collecting, archiving and processing DNA from wildlife samples using FTA® databasing paper

Abstract: Background Methods involving the analysis of nucleic acids have become widespread in the fields of traditional biology and ecology, however the storage and transport of samples collected in the field to the laboratory in such a manner to allow purification of intact nucleic acids can prove problematical.

First Documentation of In Vivo and In Vitro Ivermectin Resistance in Sarcoptes scabiei

Abstract: Ivermectin is increasingly being used to treat scabies, especially crusted (Norwegian) scabies. However, treatment failures, recrudescence, and reinfection can occur, even after multiple doses. Ivermectin resistance has been documented for some intestinal helminths in animals with intensive ivermectin exposure. Ivermectin resistance has also been induced in arthropods in laboratory experiments but, to date, has not been documented among arthropods in nature. We report clinical and in vitro evidence of ivermectin resistance in 2 patients with multiple recurrences of crusted scabies who had previously received 30 and 58 doses of ivermectin over 4 and 4.5 years, respectively. As predicted, ivermectin resistance in scabies mites can develop after intensive ivermectin use.

Neuroanatomy of extrinsic afferents supplying the gastrointestinal tract

Abstract: Here we discuss the neuroanatomy of extrinsic gastrointestinal (GI) afferent neurones, the relationship between structure and function and the role of afferents in disease. Three pathways connect the gut to the central nervous system: vagal afferents signal mainly from upper GI regions, pelvic afferents mainly from the colorectal region and splanchnic afferents from throughout. Vagal afferents mediate reflex regulation of gut function and behaviour, operating mainly at physiological levels. There are two major functional classes − tension receptors, responding to muscular contraction and distension, and mucosal receptors. The function of vagal endings correlates well with their anatomy: tracing studies show intramuscular arrays (IMAs) and intraganglionic laminar endings (IGLEs); IGLEs are now known to respond to tension. Functional mucosal receptors correlate with endings traced to the lamina propria. Pelvic afferents serve similar functions to vagal afferents, and additionally mediate both innocuous and noxious sensations. Splanchnic afferents comprise mucosal and stretch-sensitive afferents with low thresholds in addition to high-threshold serosal/mesenteric afferents suggesting diverse roles. IGLEs, probably of pelvic origin, have been identified recently in the rectum and respond similarly to gastric vagal IGLEs. Gastrointestinal afferents may be sensitized or inhibited by chemical mediators released from several cell types. Whether functional changes have anatomical correlates is not known, but it is likely that they underlie diseases involving visceral hypersensitivity.

Glucuronidation and the UDP-glucuronosyltransferases in health and disease

Abstract: This article is an updated report of a symposium held at the June 2000 annual meeting of the American Society for Pharmacology and Experimental Therapeutics in Boston. The symposium was sponsored by the ASPET Divisions for Drug Metabolism and Molecular Pharmacology. The report covers research from the authors' laboratories on the structure and regulation of UDP-glucuronosyltransferase (UGT) genes, glucuronidation of xenobiotics and endobiotics, the toxicological relevance of UGTs, the role of UGT polymorphisms in cancer susceptibility, and gene therapy for UGT deficiencies.

Enteric motor and interneuronal circuits controlling motility

Abstract: The enteric nervous system regulates intestinal motility. It contains intrinsic sensory neurones, several types of interneurones and excitatory and inhibitory motor neurones. This review summarizes our knowledge of motor neurones and interneurones in simple motility reflex pathways (ascending and descending excitation, descending inhibition) and it focuses on guinea-pig ileum. Excitatory circular muscle motor neurones contain choline acetyltransferase (ChAT) and tachykinins and project orally 0.5-10 mm. They transmit via muscarinic acetylcholine receptors and tachykinins acting at NK1 and NK2 receptors. Inhibitory circular muscle motor neurones contain nitric oxide synthase (NOS), vasoactive intestinal peptide (VIP) and pituitary adenylyl cyclase activating peptide (PACAP), project anally up to 25 mm and transmit via ATP, nitric oxide and/or VIP. Ascending interneurones project up to 10 mm orally and contain ChAT and tachykinins. They transmit to each other via ACh at nicotinic receptors (nAChR), but to excitatory motor neurones via both nAChR and NK3 receptors. There are at least three types of descending interneurones and one transmits to inhibitory motor neurones via ATP acting at P2X receptors. NOS-containing descending interneurones receive input via P2Y receptors from other interneurones. Transmission to and from the other descending interneurones (ChAT/5-HT, ChAT/somatostatin) is yet to be characterized.

Cohort study of examination performance of undergraduate medical students learning in community settings

Abstract: Objectives To determine whether moving clinical medical education out of the tertiary hospital into a community setting compromises academic standards. Design Cohort study. Setting Flinders University four year graduate entry medical course. In their third year, students are able to choose to study at the tertiary teaching hospital in Adelaide, in rural general practices, or at Royal Darwin Hospital, a regional secondary referral hospital. Participants All 371 medical students who did their year 3 study from 1998-2002. Main outcome measures Mean student examination score (%) at the end of year 3. Results The unadjusted mean year 3 scores at each location differed significantly (P Conclusions These findings show that the concern that student academic performance in the tertiary hospital would be better than that of students in the regional hospital and community settings is not justified. This challenges the orthodoxy of a tertiary hospital education being the gold standard for undergraduate medical students.

Voxel-based computational models of real human anatomy: a review.

Abstract: Computational models of human anatomy are mathematical representations of human anatomy designed to be used in dosimetry calculations. They have been used in dosimetry calculations for radiography, radiotherapy, nuclear medicine, radiation protection and to investigate the effects of low frequency electromagnetic fields. Tomographic medical imaging techniques have allowed the construction of digital three-dimensional computational models based on the actual anatomy of individual humans. These are called voxel models, tomographic models or phantoms. Their usefulness lies in their faithful representation of human anatomy and the flexibility they afford by being able to be scaled in size to match the required human dimensions. Segmenting medical images in order to make voxel models is very time-consuming so semi-automatic segmentation techniques are being developed. Some 21 whole or partial body models currently exist and more are being prepared. These models are listed and discussed.

An international perspective on heart failure and left ventricular systolic dysfunction complicating myocardial infarction: the VALIANT registry

Abstract: Aims We analysed the contemporary incidence, outcomes, and predictors of heart failure (HF) and/or left ventricular systolic dysfunction (LVSD) before discharge in patients with acute myocardial infarction (MI). The baseline presence of HF or LVSD, or its development during hospitalisation, increases short- and long-term risk after MI, yet its incidence, predictors, and outcomes have not been well described in a large, international, general. MI population. Methods and results The VALIANT registry included 5573 consecutive MI patients at 84 hospitals in nine countries from 1999 to 2001. A multivariable logistic survival model was constructed using baseline variables to determine the adjusted mortality risk for those with in-hospital HF and/or LVSD. Baseline variables were also tested for associations with in-hospital HF and/or LVSD. Of the 5566 patients analysed, 42% had HF and/or LVSD during hospitalisation. Their in-hospital. mortality rate was 13.0% compared with 2.3% for those without HF and/or without LVSD. After adjustment for other baseline risk factors, in-hospital HF and/or LVSD carried a hazard ratio for inhospital mortality of 4.12 (95% confidence interval: 3.08-5.56). Patients with HF and/or LVSD also had disproportionately higher rates of other cardiovascular events. Conclusions HF and/or LVSD is common in the general contemporary MI population and precedes 80.3% of all in-hospital deaths after MI. Survivors of early MI-associated HF and/or LVSD have more complications, Longer hospitalisations, and are more likely to die during hospitalisation. Although baseline variables can identify MI patients at highest risk for HF and/or LVSD, such patients are less likely to receive indicated procedures and medical therapies. (C) 2004 The European Society of Cardiology. Published by Elsevier Ltd. All rights reserved.

Predicting Human Drug Glucuronidation Parameters: Application of In Vitro and In Silico Modeling Approaches

Abstract: Cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT), which both exist as enzyme "superfamilies," are together responsible for the metabolism of most hepatically cleared drugs. There is currently intense interest in the development of techniques that permit identification of the CYP and UGT isoform(s) involved in the metabolism of a newly discovered drug, and hence prediction of factors likely to alter elimination in vivo. In addition, the quantitative scaling of kinetic parameters for a metabolic pathway assumes importance for identifying newly discovered drugs with undesirable in vivo pharmacokinetic properties. Although qualitative and quantitative in vitro-in vivo correlation based on data generated using human liver tissue or recombinant enzymes have been applied successfully to many drugs eliminated by CYP, these strategies have proved less definitive for glucuronidated compounds. Computational (in silico) modeling techniques that potentially provide a facile and economic alternative to the in vitro methods are now emerging. This review assesses the utility of in vitro and in silico approaches for the qualitative and quantitative prediction of drug glucuronidation parameters and the challenges facing the development of generalizable models.

Use of microcosms to determine persistence of Escherichia coli in recreational coastal water and sediment and validation with in situ measurements

Abstract: D . L . C R A I G , H . J . F A L L O W F I E L D A N D N . J . C R O M A R . 2004. Aims: To determine the persistence of the faecal indicator organism Escherichia coli in recreational coastal water and sediment using laboratory-based microcosms and validation with in situ measurements. Methods and Results: Intact sediment cores were taken from three distinct coastal sites. Overlying estuarine water was inoculated with known concentrations of E. coli and decay rates from both overlying water and sediment were determined following enumeration by the membrane filtration method at fixed time intervals over a 28-day period. It was demonstrated that E. coli may persist in coastal sediment for >28 days when incubated at 10� C. Escherichia coli survival was found to have an inverse relationship with temperature in both water and sediment. In general the decay rate for E. coli was greater in water than in sediment. Small particle size and high organic carbon content were found to enhance E. coli survival in coastal sediments in the microcosms. Conclusions: Results of this microcosm study demonstrated the more prolonged survival of E. coli in coastal sediments compared with overlying water, which may imply an increased risk of exposure because of the possible resuspension of pathogenic micro-organisms during natural turbulence or human recreational activity. Significance and Impact of the Study: A more accurate estimate of exposure risk has been described which may subsequently be used in a quantitative microbial risk assessment for recreational coastal waters.

Thermosensitive transient receptor potential channels in vagal afferent neurons of the mouse

Abstract: A number of transient receptor potential (TRP) channels has recently been shown to mediate cutaneous thermosensitivity. Sensitivity to warm and cool stimuli has been demonstrated in both human and animal gastrointestinal tract; however, the molecular mechanisms that underlie this have not been determined. Vagal afferent neurons with cell bodies in the nodose ganglion are known to mediate nonnociceptive sensation from the upper gut. In this study, isolated cultured nodose ganglion from the mouse neurons showed changes in cytoplasmic-free Ca(2+) concentrations over a range of temperatures, as well as to icilin (a TRPM8 and TRPN1 agonist) and capsaicin (a TRPV1 agonist). RT-PCR was used to show the presence of six temperature-sensitive TRP channel transcripts (TRPV1-4, TRPN1, and TRPM8) in whole nodose ganglia. In addition, RT-PCR of single nodose cell bodies, which had been retrogradely labeled from the upper gut, detected transcripts for TRPV1, TRPV2, TRPV4, TRPN1, and TRPM8 in a proportion of cells. Immunohistochemical labeling detected TRPV1 and TRPV2 proteins in nodose ganglia. The presence of TRP channel transcripts and proteins was also detected in cells within several regions of the gastrointestinal tract. Our results reveal that TRP channels are present in subsets of vagal afferent neurons that project to the stomach and may confer temperature sensitivity on these cells.

Analysis of the endophytic actinobacterial population in the roots of wheat (Triticum aestivum L.) by terminal restriction fragment length polymorphism and sequencing of 16S rRNA clones.

Abstract: The endophytic actinobacterial population in the roots of wheat grown in three different soils obtained from the southeast part of South Australia was investigated by terminal restriction fragment length polymorphism (T-RFLP) analysis of the amplified 16S rRNA genes. A new, validated approach was applied to the T-RFLP analysis in order to estimate, to the genus level, the actinobacterial population that was identified. Actinobacterium-biased primers were used together with three restriction enzymes to obtain terminal restriction fragments (TRFs). The TRFs were matched to bacterial genera by the T-RFLP Analysis Program, and the data were analyzed to validate and semiquantify the genera present within the plant roots. The highest diversity and level of endophytic colonization were found in the roots of wheat grown in a dark loam from Swedes Flat, and the lowest were found in water-repellent sand from Western Flat. This molecular approach detected a greater diversity of actinobacteria than did previous culture-dependent methods, with the predominant genera being Mycobacterium (21.02%) in Swedes Flat, Streptomyces (14.35%) in Red Loam, and Kitasatospora (15.02%) in Western Flat. This study indicates that the soil that supported a higher number of indigenous organisms resulted in wheat roots with higher actinobacterial diversity and levels of colonization within the plant tissue. Sequencing of 16S rRNA clones, obtained using the same actinobacterium-biased PCR primers that were used in the T-RFLP analysis, confirmed the presence of the actinobacterial diversity and identified a number of Mycobacterium and Streptomyces species.