22,324 results for 2000, Journal article

  • An ovine transgenic Huntington's disease model

    Jacobsen, Jessie; Bawden, CS; Rudiger, SR; McLaughlan, CJ; Reid, Susanne; Waldvogel, Henry; MacDonald, ME; Gusella, JF; Walker, SK; Kelly, JM; Webb, GC; Faull, Richard; Rees, Mark; Snell, Russell (2010)

    Journal article
    The University of Auckland Library

    Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disorder caused by an expansion of a CAG trinucleotide repeat in the huntingtin (HTT) gene [Huntington's Disease Collaborative Research Group (1993) A novel gene containing a trinucleotide repeat that is expanded and unstable on Huntington's disease chromosomes. The Huntington's Disease Collaborative Research Group. Cell, 72, 971???983]. Despite identification of the gene in 1993, the underlying life-long disease process and effective treatments to prevent or delay it remain elusive. In an effort to fast-track treatment strategies for HD into clinical trials, we have developed a new large-animal HD transgenic ovine model. Sheep, Ovis aries L., were selected because the developmental pattern of the ovine basal ganglia and cortex (the regions primarily affected in HD) is similar to the analogous regions of the human brain. Microinjection of a full-length human HTT cDNA containing 73 polyglutamine repeats under the control of the human promotor resulted in six transgenic founders varying in copy number of the transgene. Analysis of offspring (at 1 and 7 months of age) from one of the founders showed robust expression of the full-length human HTT protein in both CNS and non-CNS tissue. Further, preliminary immunohistochemical analysis demonstrated the organization of the caudate nucleus and putamen and revealed decreased expression of medium size spiny neuron marker DARPP-32 at 7 months of age. It is anticipated that this novel transgenic animal will represent a practical model for drug/clinical trials and surgical interventions especially aimed at delaying or preventing HD initiation. New sequence accession number for ovine HTT mRNA: FJ457100.

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  • Randomized phase III placebo-controlled trial of carboplatin and paclitaxel with or without the vascular disrupting agent vadimezan (ASA404) in advanced non-small-cell lung cancer.

    Lara, PN; Douillard, JY; Nakagawa, K; von Pawel, J; McKeage, Mark; Albert, I; Losonczy, G; Reck, M; Heo, DS; Fan, X; Fandi, A; Scagliotti, G (2011)

    Journal article
    The University of Auckland Library

    This phase III trial was conducted to test whether the novel vascular disrupting agent ASA404 (vadimezan), when combined with first-line platinum-based chemotherapy, improves survival in patients with advanced non-small-cell lung cancer (NSCLC) versus chemotherapy alone.

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  • Cellular characterization of magnetic resonance imaging (MRI) bone edema in rheumatoid arthritis; implications for pathogenesis of erosive disease

    Dalbeth, Nicola; Smith, T; Gray, S; Doyle, Anthony; Antill, Pamela; Lobo, M; Robinson, Elizabeth; King, A; Cornish, Jillian; Shalley, Gareth; Gao, A; McQueen, Fiona (2009)

    Journal article
    The University of Auckland Library

    Objectives: Magnetic resonance imaging (MRI) bone oedema is an important predictor of bone erosion in rheumatoid arthritis (RA). This study aimed to determine the cellular components of MRI bone oedema, and clarify the relationship between bone erosion and MRI bone oedema. Methods: Twenty-eight bones from 11 patients with RA undergoing orthopaedic surgery were analysed by quantitative and semi-quantitative immunohistochemistry. Pre-operative contrast-enhanced MRI scans were analysed for bone oedema. Results: The density of osteoclasts was higher in those samples with MRI bone oedema than those without MRI bone oedema (p???=???0.01). Other cells identified within bone marrow included macrophages and plasma cells, and these were more numerous in samples with MRI bone oedema (p???=???0.02 and 0.05 respectively). B cells were present in lower numbers, but B cell aggregates were identified in some samples with MRI bone oedema. There was a trend to increased RANKL expression in samples with MRI bone oedema (p???=???0.09). Expression of RANKL correlated with the number of osteoclasts (r???=???0.592, p???=???0.004). Conclusions: The increased number of osteoclasts and RANKL expression in samples with MRI bone oedema supports the hypothesis that bone erosion in RA occurs through activation of local bone resorption mechanisms within subchondral bone as well as through synovial invasion into bone.

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  • The atomic structure of baculovirus polyhedra reveals the independent emergence of infectious crystals in DNA and RNA viruses

    Coulibaly, F; Cooper, Yui; Gutmann, S; Rajendran, C; Haebel, PW; Ikeda, K; Mori, H; Ward, VK; Schulze-Briese, C; Metcalf, Peter (2009)

    Journal article
    The University of Auckland Library

    Baculoviruses are ubiquitous insect viruses well known for their use as bioinsecticides, gene therapy vectors, and protein expression systems. Overexpression of recombinant proteins in insect cell culture utilizes the strong promoter of the polyhedrin gene. In infected larvae, the polyhedrin protein forms robust intracellular crystals called polyhedra, which protect encased virions for prolonged periods in the environment. Polyhedra are produced by two unrelated families of insect viruses, baculoviruses and cypoviruses. The atomic structure of cypovirus polyhedra revealed an intricate packing of trimers, which are interconnected by a projecting N-terminal helical arm of the polyhedrin molecule. Baculovirus and cypovirus polyhedra share nearly identical lattices, and the N-terminal region of the otherwise unrelated baculovirus polyhedrin protein sequence is also predicted to be ??-helical. These results suggest homology between the proteins and a common structural basis for viral polyhedra. Here, we present the 2.2-?? structure of baculovirus polyhedra determined by x-ray crystallography from microcrystals produced in vivo. We show that the underlying molecular organization is, in fact, very different. Although both polyhedra have nearly identical unit cell dimensions and share I23 symmetry, the polyhedrin molecules are structurally unrelated and pack differently in the crystals. In particular, disulfide bonds and domain-swapped N-terminal domains stabilize the building blocks of baculovirus polyhedra and interlocking C-terminal arms join unit cells together. We show that the N-terminal projecting helical arms have different structural roles in baculovirus and cypovirus polyhedra and conclude that there is no structural evidence for a common evolutionary origin for both classes of polyhedra

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  • Sleep Environment Risk Factors for Sudden Infant Death Syndrome: The German Sudden Infant Death Syndrome Study

    Vennemann, MM; Bajanowski, T; Brinkmann, B; Jorch, G; Sauerland, C; Mitchell, Edwin; GeSID Study Grp (2009-04)

    Journal article
    The University of Auckland Library

    OBJECTIVE. Our goal was to investigate the risk factors for sudden infant death syndrome in the infants' sleep environment for a population in which few infants sleep prone as a result of education campaigns. METHODS. This was a population-based sudden infant death syndrome case-control study over 3 years (1998???2001) in Germany. RESULTS. There were 333 sudden infant death syndrome cases and 998 matched controls. Although only 4.1% of the infants were placed prone to sleep, those infants were at a high risk of sudden infant death syndrome. Those who were unaccustomed to sleeping prone were at very high risk, as were those who turned to prone. Bed sharing (especially for infants younger than 13 weeks); duvets; sleeping prone on a sheepskin; sleeping in the house of a friend or a relative (compared with sleeping in the parental home); and sleeping in the living room (compared with sleeping in the parental bedroom) increased the risk for sudden infant death syndrome; pacifier use during the last sleep was associated with a significantly reduced risk of sudden infant death syndrome. CONCLUSIONS. This study has clarified the risk factors for sudden infant death syndrome in a population where few infants sleep prone. This study supports the current recommendations of the American Academy of Pediatrics. This study has identified several novel risk factors for sudden infant death syndrome: an increased risk if the infants sleeps outside the parental home, death in the living room, and the high risk when sleeping prone on a sheepskin; however, because the numbers of cases in these groups are small, additional studies are needed to confirm these findings.

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  • Long term trends of stand transpiration in a remnant forest during wet and dry years

    Zeppel, MJB; Ng, Catriona; Yunusa, IAM; Whitley, RJ; Eamus, D (2008)

    Journal article
    The University of Auckland Library

    Daily and annual rates of stand transpiration in a drought year and a non-drought year are compared in order to understand the adaptive responses of a remnant woodland to drought and predict the effect of land use change. Two methods were used to estimate stand transpiration. In the first, the ratio of sap velocity of a few trees measured for several hundred days to the mean sap velocity of many trees measured during brief sampling periods (generally 6???7 trees for 5 or 6 days), called the Esv method is used to scale temporally from the few intensive study periods. The second method used was the Penman???Monteith (P???M) equation (called the EPM method). Weather variables and soil moisture were used to predict canopy conductance, which in turn was used to predict daily and annual stand transpiration. Comparisons of daily transpiration estimated with the two methods showed larger values for the EPM method during a drought year and smaller values for the EPM when the rainfall was above average. Generally, though, annual estimates of stand transpiration were similar using the two methods. The Esv method produced an estimate of 318 mm (61% of rainfall) in the drought year and 443 mm (42%) in the year having above average rainfall. The EPM method estimated stand transpiration as 379 mm (73%) and 398 mm (37%), respectively, for the two years. Both estimates of annual stand transpiration demonstrated that the remnant forest showed resilience to an extreme and long-term drought. More importantly, the annual estimates showed that in dry years a larger proportion of rainfall was used as transpiration, and groundwater recharge was absent but in years with above average rainfall recharge was significantly increased. Changes in leaf area index were minimal between years and changes in stomatal conductance were the dominant mechanism for adapting to the drought. The remnant forest rapidly responded to increased water availability after the drought through a new flush of leaves and increased stomatal conductance.

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  • Intelligent Component - based Automation of Baggage Handling Systems with IEC 61499

    Black, Geoffrey; Vyatkin, Valeriy (2010)

    Journal article
    The University of Auckland Library

    Airport baggage handling is a field of automation systems that is currently dependent on centralized control systems and conventional automation programming techniques. In this and other areas of manufacturing and materials handling, these legacy automation technologies are increasingly limiting for the growing demand for systems that are reconfigurable, fault tolerant, and easy to maintain. IEC 61499 Function Blocks is an emerging architectural framework for the design of distributed industrial automation systems and their reusable components. A number of architectures have been suggested for multiagent and holonic control systems that incorporate function blocks. This paper presents a multiagent control approach for a baggage handling system (BHS) using IEC 61499 Function Blocks. In particular, it focuses on demonstrating a decentralized control system that is scalable, reconfigurable, and fault tolerant. The design follows the automation object approach, and produces a function block component representing a single section of conveyor. In accordance with holonic principles, this component is autonomous and collaborative, such that the structure and the behavior of a BHS can be entirely defined by the interconnection of these components within the function block design environment. Simulation is used to demonstrate the effectiveness of the agent-based control system and a utility is presented for real-time viewing of these systems. Tests on a physical conveyor test system demonstrated deployment to embedded control hardware.

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  • Fatty acid chain length, postprandial satiety and food intake in lean men.

    Poppitt, Sally; Strik, CM; MacGibbon, AK; McArdle, Brian; Budgett, Stephanie; McGill, Anne-Thea (2010)

    Journal article
    The University of Auckland Library

    High-fat diets are associated with obesity, and the weak satiety response elicited in response to dietary lipids is likely to play a role. Preliminary evidence from studies of medium (MCT) and long chain triglycerides (LCT) supports greater appetite suppression on high-MCT diets, possibly a consequence of direct portal access, more rapid oxidation and muted lipaemia. No data is as yet available on high-SCT diets which also have direct hepatic access. In this study SCT- (dairy fats), MCT- (coconut oil) and LCT-enriched (beef tallow) test breakfasts (3.3 MJ) containing 52 g lipid (58 en% fat) were investigated in a randomized, cross-over study in 18 lean men. All participants were required to complete the 3 study days in randomised order. Participants rated appetite sensations using visual analogue scales (VAS), and energy intake (EI) was measured by covert weighing of an ad libitum lunch meal 3.5 h postprandially. Blood samples were collected by venous cannulation. There were no detectable differences between breakfasts in perceived pleasantness, visual appearance, smell, taste, aftertaste and palatability (P>0.05). There was no significant effect of fatty acid chain length on ratings of hunger, fullness, satisfaction or current thoughts of food, nor did energy (mean, sem: SCT: 4406, 366 kJ; MCT: 4422, 306 kJ; LCT: 4490, 324 kJ; P>0.05) or macronutrient intake at lunch differ between diets. The maximum difference in EI between diets was less than 2%. Postprandial lipaemia also did not differ significantly. We conclude that there was no evidence that fatty acid chain length has an effect on measures of appetite and food intake when assessed following a single high-fat test meal in lean participants.

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  • A single-blind, randomized, crossover trial of the effects of a nicotine pouch on the relief of tobacco withdrawal symptoms and user satisfaction.

    Thornley, Simon; McRobbie, Hayden; Lin, Ruey; Bullen, Christopher; Hajek, P; Laugesen, M; Senior, Hugh; Whittaker, Robyn (2009)

    Journal article
    The University of Auckland Library

    Introduction We compared the effects of a 4-mg oral nicotine pouch (Zonnic pouch), with nicotine chewing gum and placebo pouch, on withdrawal discomfort after overnight tobacco abstinence. We also assessed participants??? preferences, satisfaction, and consumption patterns. Methods This was a randomized, placebo-controlled, three-way crossover study of 30 adult smokers. After overnight tobacco abstinence, subjects reported on a Visual Analog Scale (VAS; 0???100) tobacco withdrawal symptoms (craving, irritability, difficulty concentrating, and restlessness) before use and during the first hour after first product use. They then used the product throughout the study day and in the evening reported product usefulness, temporary abstinence success, and satisfaction. Results In a multivariate analysis, area under the curve (craving vs. time) was reduced by 23 points 60 min after taking the study medication in the nicotine pouch group, compared with 15- and 8-point decreases in the gum and placebo groups, respectively. The difference in craving ratings between the pouch and placebo was significant (p???=???.002). Nicotine pouch reduced irritability more than gum (difference???=???9.86; p???=???.01). For pouch users, the odds ratio for temporary tobacco abstinence (21.5 hr) during study days (compared with gum) was 2.8 (95% CI???=???0.8???8.1). Compared with the gum, the pouch was rated as significantly more ???helpful to stop smoking??? (difference???=???20.6; 95% CI???=???2.4???38.9) and ???pleasant to use??? (difference???=???17.3; 95% CI???=???2.6???32.0). Discussion The Zonnic pouch appears to be as effective at relieving craving as nicotine gum and was subjectively favored over the gum. These results suggest that the pouch will be a helpful addition to the range of existing nicotine replacement treatments.

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  • Mycoviruses of filamentous fungi and their relevance to plant pathology

    Pearson, Michael; Beever, RE; Boine, B; Arthur, K (2009-01)

    Journal article
    The University of Auckland Library

    Mycoviruses (fungal viruses) are reviewed with emphasis on plant pathogenic fungi. Based on the presence of virus-like particles and unencapsidated dsRNAs, mycoviruses are common in all major fungal groups. Over 80 mycovirus species have been officially recognized from ten virus families, but a paucity of nucleic acid sequence data makes assignment of many reported mycoviruses difficult. Although most of the particle types recognized to date are isometric, a variety of morphologies have been found and, additionally, many apparently unencapsidated dsRNAs have been reported. Until recently, most characterized mycoviruses have dsRNA genomes, but ssRNA mycoviruses now constitute about one-third of the total. Two hypotheses for the origin of mycoviruses of plant pathogens are discussed: the first that they are of unknown but ancient origin and have coevolved along with their hosts, the second that they have relatively recently moved from a fungal plant host into the fungus. Although mycoviruses are typically readily transmitted through asexual spores, transmission through sexual spores varies with the host fungus. Evidence for natural horizontal transmission has been found. Typically, mycoviruses are apparently symptomless (cryptic) but beneficial effects on the host fungus have been reported. Of more practical interest to plant pathologists are those viruses that confer a hypovirulent phenotype, and the scope for using such viruses as biocontrol agents is reviewed. New tools are being developed based on host genome studies that will help to address the intellectual challenge of understanding the fungal???virus interactions and the practical challenge of manipulating this relationship to develop novel biocontrol agents for important plant pathogens.

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  • Orchid pollination by sexual deception: pollinator perspectives

    Gaskett, Anne (2011)

    Journal article
    The University of Auckland Library

    The extraordinary taxonomic and morphological diversity of orchids is accompanied by a remarkable range of pollinators and pollination systems. Sexually deceptive orchids are adapted to attract specific male insects that are fooled into attempting to mate with orchid flowers and inadvertently acting as pollinators. This review summarises current knowledge, explores new hypotheses in the literature, and introduces some new approaches to understanding sexual deception from the perspective of the duped pollinator. Four main topics are addressed: (1) global patterns in sexual deception, (2) pollinator identities, mating systems and behaviours, (3) pollinator perception of orchid deceptive signals, and (4) the evolutionary implications of pollinator responses to orchid deception, including potential costs imposed on pollinators by orchids. A global list of known and putative sexually deceptive orchids and their pollinators is provided and methods for incorporating pollinator perspectives into sexual deception research are provided and reviewed. At present, almost all known sexually deceptive orchid taxa are from Australia or Europe. A few sexually deceptive species and genera are reported for New Zealand and South Africa. In Central and Southern America, Asia, and the Pacific many more species are likely to be identified in the future. Despite the great diversity of sexually deceptive orchid genera in Australia, pollination rates reported in the literature are similar between Australian and European species. The typical pollinator of a sexually deceptive orchid is a male insect of a species that is polygynous, monandrous, haplodiploid, and solitary rather than social. Insect behaviours involved in the pollination of sexually deceptive orchids include pre-copulatory gripping of flowers, brief entrapment, mating, and very rarely, ejaculation. Pollinator behaviour varies within and among pollinator species. Deception involving orchid mimicry of insect scent signals is becoming well understood for some species, but visual and tactile signals such as colour, shape, and texture remain neglected. Experimental manipulations that test for function, multi-signal interactions, and pollinator perception of these signals are required. Furthermore, other forms of deception such as exploitation of pollinator sensory biases or mating preferences merit more comprehensive investigation. Application of molecular techniques adapted from model plants and animals is likely to deliver new insights into orchid signalling, and pollinator perception and behaviour. There is little current evidence that sexual deception drives any species-level selection on pollinators. Pollinators do learn to avoid deceptive orchids and their locations, but this is not necessarily a response specific to orchids. Even in systems where evidence suggests that orchids do interfere with pollinator mating opportunities, considerable further research is required to determine whether this is sufficient to impose selection on pollinators or generate antagonistic coevolution or an arms race between orchids and their pollinators. Botanists, taxonomists and chemical ecologists have made remarkable progress in the study of deceptive orchid pollination. Further complementary investigations from entomology and behavioural ecology perspectives should prove fascinating and engender a more complete understanding of the evolution and maintenance of such enigmatic plant-animal interactions.

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  • Comorbidity of auditory processing, language, and reading disorders

    Sharma, M; Purdy, Suzanne; Kelly, AS (2009)

    Journal article
    The University of Auckland Library

    Purpose: The authors assessed comorbidity of auditory processing disorder (APD), language impairment ( LI), and reading disorder (RD) in school-age children. Method: Children (N = 68) with suspected APD and nonverbal IQ standard scores of 80 or more were assessed using auditory, language, reading, attention, and memory measures. Auditory processing tests included the Frequency Pattern Test (FPT; F. E. Musiek, 1994; D. Noffsinger, R. H. Wilson, & F. E. Musiek, 1994); the Dichotic Digit Test Version 2 (DDT; F. E. Musiek, 1983); the Random Gap Detection Test (R.W. Keith, 2000); the 500-Hz tone Masking Level Difference (V. Aithal, A. Yonovitz, & S. Aithal, 2006); and a monaural low-redundancy speech test (compressed and reverberant words; A. Boothroyd & S. Nittrouer, 1988). The Clinical Evaluation of Language Fundamentals, Fourth Edition (E. Semel, E.Wiig, &W. Secord, 2003) was used to assess language abilities (including auditory memory). Reading accuracy and fluency and phonological awareness abilities were assessed using the Wheldall Assessment of Reading Passages (A. Madelaine & K. Wheldall, 2002) and the Queensland University Inventory of Literacy (B. Dodd, A. Holm, M. Orelemans, & M. McCormick, 1996). Attention was measured using the Integrated Visual and Auditory Continuous Performance Test (J. A. Sandford & A. Turner, 1995). Results: Of the children, 72% had APD on the basis of these test results. Most of these children (25%) had difficulty with the FPT bilaterally. A further 22% had difficulty with the FPT bilaterally and had right ear deficits for the DDT. About half of the children (47%) had problems in all 3 areas (APD, LI, and RD); these children had the poorest FPT scores. More had APD-RD, or APD-LI, than APD, RD, or LI alone. There were modest correlations between FPT scores and attention and memory, and between DDT scores and memory. Conclusions: LI and RD commonly co-occur with APD. Attention and memory are linked to performance on some auditory processing tasks but only explain a small amount of the variance in scores. Comprehensive assessment across a range of areas is required to characterize the difficulties experienced by children with APD.

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  • Physicochemical properties of bread dough with added pectin fibre and phenolic antioxidants

    Satchithananthasivam, Anusooya; Sun-Waterhouse, Dongxiao; Waterhouse, Geoffrey; Quek, Siew-Young; Perera, Conrad (2011-01-19)

    Journal article
    The University of Auckland Library

    Comparative studies were conducted in this paper to investigate the effects of added dietary fiber (DF) and/orcphenolic antioxidants on the properties of bread dough and finished bread. Breads were developed in the absence (control bread), or presence of apple pectin and/or fruit phenolic extracts (treated breads), and subjected to quality evaluation (attributes including color, weight, and volume) and characterization of chemical and rheological properties. Chemical analyses revealed that breads with added phenolic extracts had greater antioxidant activity and higher extractable phenolic content, than control bread and the treated breads with added apple pectin(s). The measured antioxidant activity was mainly derived from the phenolics present in bread. Storage modulus G (elasticity) and loss modulus G (viscocity) of the treated bread dough with added pectin(s) only were higher than those of control dough. The G' or G" of the treated breads incorporated with a combination of a pectin and fruit phenolic extract depended on the type of phenolic extract (that is, apple and blackcurrant extracts behaved differently from kiwifruit extract). The G' and G" at the final baking step were higher than those of other stages, indicating an increase in cross-linking among polymeric molecules and bread particles of high molecular weight. We conclude that the added pectin and/or phenolic extract had influenced bread dough cross-linking microstructure and bread properties through being involved in the interactions with bread components such as wheat proteins during dough development and bread baking.

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  • Medical students' attitudes towards peer physical examination: findings from an international cross-sectional and longitudinal study

    Rees, CE; Wearn, Andrew; Vnuk, A; Sato, TJ (2009)

    Journal article
    The University of Auckland Library

    Although studies have begun to shed light on medical students??? attitudes towards peer physical examination (PPE), they have been conducted at single sites, and have generally not examined changes in medical students??? attitudes over time. Employing both cross-sectional and longitudinal designs, the current study examines medical students??? attitudes towards PPE at schools from different geographical and cultural regions and assess changes in their attitudes over their first year of medical study. Students at six schools (Peninsula, UK; Durham, UK; Auckland, New Zealand; Flinders, Australia; Sapporo, Japan and Li Ka Shing, Hong Kong) completed the Examining Fellow Students (EFS) questionnaire near the start of their academic year (T1), and students at four schools (Peninsula, Durham, Auckland and Flinders) completed the EFS for a second time, around the end of their academic year (T2). Univariate and multivariate analyses revealed a high level of acceptance for PPE of non-intimate body regions amongst medical students from all schools (greater than 83%, hips, at T1 and 94.5%, hips and upper body, at T2). At T1 and T2, students??? willingness to engage in PPE was associated with their gender, ethnicity, religiosity and school. Typically, students least comfortable with PPE at T1 and T2 were female, non-white, religious and studying at Auckland. Although students??? attitudes towards PPE were reasonably stable over their first year of study, and after exposure to PPE, we did find some statistically significant differences in attitudes between T1 and T2. Interestingly, attitude changes were consistently predicted by gender, even when controlling for school. While male students??? attitudes towards PPE were relatively stable over time, females??? attitudes were changeable. In this paper, we discuss our findings in light of existing research and theory, and discuss their implications for educational practice and further research.

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  • Energy and the tempo of evolution in amphibians

    Wright, Shane; Gillman, LN; Ross, Howard; Keeling, Diana (2010-09)

    Journal article
    The University of Auckland Library

    Aim??? The evolutionary speed hypothesis (ESH) attempts to explain global patterns of species richness on the basis that rates of molecular evolution and speciation in warmer climates have led to a greater accumulation of taxa at lower latitudes. A substantial alternative hypothesis to the ESH is the tropical conservatism hypothesis (TCH). However, recent tests of the TCH, using amphibians as the model taxon, have relied on the assumption that rates of molecular evolution are stable across latitudes and elevations. Here, we test for the first time for systematic variation in rates of molecular evolution across latitude and elevation among amphibians. Location??? The dataset is geographically diverse with samples from all continents except Antarctica and also from many of the earth's major tropical???warm temperate archipelagos. Methods??? We tested for substitution rate heterogeneity across climatically varying habitats with the mitochondrial RNA genes 12S and 16S. Thus, we report here on our findings for amphibians ??? a taxon whose phylogenetic and trophic contexts are remote from those previously tested ??? using genes that have also not been examined before. The study utilized paired contrasts of sister species (188 species across 18 families, including both caudates and anurans) that are spatially separated in either latitudinal or elevational dimensions. Results??? We found substantially faster substitution rates for species living in warmer habitats (P= 0.001???0.002) at both lower latitudes (P < 0.02) and lower elevations (P < 0.01). Main conclusions??? The consistency of these results with the previous studies that used quite different organisms ??? and in this instance also using different genes ??? suggests that this is a ubiquitous pattern in nature consistent with the predictions of the ESH. Recent tests of the TCH that, in estimating diversification rates, have relied on the assumption that DNA evolution occurs at a constant rate across latitudes and elevations, require reconsideration in light of the findings presented here. Our results indicate that greater caution is required when estimating dates of divergence using DNA sequence data.

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  • Once-daily Gentamicin in Infants and Children A Prospective Cohort Study Evaluating Safety and the Role of Therapeutic Drug Monitoring in Minimizing Toxicity

    Best, Emma; Gazarian, M; Cohn, R; Wilkinson, M; Palasanthiran, P (2011-10)

    Journal article
    The University of Auckland Library

    Background: The clinical evidence base for ototoxicity and nephrotoxicity outcomes with once-daily dosing (ODD) of gentamicin in children is suboptimal. Therapeutic drug monitoring (TDM) in once-daily gentamicin regimens is variable and its role in predicting or preventing clinical toxicity is unclear. We aimed to assess the safety of ODD of gentamicin and the usefulness of TDM in a pediatric cohort. Methods: Children with suspected sepsis were prospectively enrolled to receive ODD of gentamicin at 7 mg/kg/day. Hearing and renal function were objectively assessed at baseline, during therapy, and after therapy. TDM was performed using an interval-adjusted graphical method (Hartford nomogram). Results: A total of 79 children (median age: 5.6 years; range: 1 month???16 years) received 106 episodes of therapy. In all, 61% of these episodes were for febrile neutropenia. Evaluation was complete in 88% for ototoxicity and 92% for nephrotoxicity. Two patients (1.88%, 95% con???dence interval: 0.10%???7.13%) experienced permanent hearing loss. One patient (0.94%, 95% con???dence interval: 0.10%???5.73%) experienced transient nephrotoxicity. No abnormal serum gentamicin values were detected, even in those experiencing toxicity. Children experiencing toxicity were undergoing treatment for malignancies and had received nephrotoxic or ototoxic medicines before gentamicin. Conclusions: In this pediatric cohort receiving ODD of gentamicin, nephrotoxicity was uncommon and reversible, but irreversible ototoxicity occurred more frequently. TDM using a nomogram neither predicted nor prevented toxicity, which was only observed in those with risk factors

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  • The ABC of New Zealand's ten year vision for pharmacists: Awareness, barriers and consultation

    Scahill, S; Harrison, Jeffrey; Sheridan, Jane (2009)

    Journal article
    The University of Auckland Library

    Objectives This study aimed to determine New Zealand pharmacists' awareness of, recall of consultation about, and potential barriers to the implementation of the Focus on the Future: Ten Year Vision for Pharmacists in New Zealand: 2004???2014 document. Method A national postal survey was carried out in New Zealand of practising pharmacists registered with the Pharmacy Council of New Zealand (n = 1892). The survey was conducted between September and December 2006. Key findings The response rate was 51.8% (n = 980 usable surveys). Approximately three???quarters (73.4%) reported being aware of the 10???year vision document and 40.9% recall being consulted. Fewer than one???third (29.8%) had read the document prior to completing the survey. Thirty???two variables describing potential barriers to implementing the 10???year vision were reduced, through factor analysis, to seven factors with significant eigenvalues (>1.0). The factors describe the underlying themes of barriers identified in the survey, including pharmacist humanistic, integrated systems of care and teamwork, funder stakeholder relationships and remuneration, lack of appreciation of knowledge and skills, lack of research support, current expertise and continuing professional development, and lack of voice. The majority of barrier variables within the seven factors were rated as extremely or quite important. Conclusions There was a high level of awareness and moderate level of recall of consultation on the document among respondents. Although 40% recall being consulted on the document, fewer than one???third reported having read the document prior to completing our survey. Pharmacists highlighted a significant number of potential barriers to the implementation of the 10???year vision. If the pharmacy profession in New Zealand is to move forward towards the state described in the 10???year vision document then these potential barriers need to be better understood and addressed.

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  • Depression in older people: visual impairment and subjective ratings of health.

    Hayman, Karen; Kerse, Ngaire; La Grow, SJ; Wouldes, Trecia; Robertson, M; Campbell, AJ (2007)

    Journal article
    The University of Auckland Library

    Purpose. The aim of this study was to establish the prevalence of depression in a sample of older adults with impaired vision and investigate associations between physical and visual disability and depression. Methods. We analyzed cross-sectional baseline data from 391 participants aged >=75 years with visual acuity of 6/24 (20/80) or less, recruited for a randomized controlled trial of interventions to prevent falls (the VIP trial). Measures included the geriatric depression scale (GDS-15), the state-trait anxiety index, activities of daily living (Nottingham extended ADL scale), physical activity (human activity profile), an index of visual functioning (VF-14), health-related quality of life (SF-36), objective measures of physical ability, and a measure of visual acuity. Regression models were developed to investigate the association between depression scores and physical, psychological, and visual disability. Results. About 29.4% (115 of 391) of participants were identified as potentially depressed (GDS-15 score >4). Physical function, physical activity, physical ability, visual function, anxiety, and self-reported physical and mental health were significantly worse for those with depressive symptomatology. Physical, visual, and psychological factors collectively explained 41% of the variance in the depression score in a linear regression model (R2 = 0.421, adjusted R2 = 0.410, F (7,382) = 39.680, p < 0.001). Depression was not related to age, gender, living situation, ethnicity, or number of prescription or antidepressant medications taken. Conclusions. Depression was common in this population of older adults with severe visual impairment. Impaired visual and physical functions were associated with symptoms of depression. The effect of visual disability was independent of the effect of physical disability. The strength of this relationship, and the results of the regression analyses, indicate that a person who is visually or physically disabled is more likely to suffer from depression.

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  • Estimating the number of whales entering trade using DNA profiling and capture-recapture analysis of market products

    Baker, Charles; Cooke, J; Lavery, Shane; Dalebout, ML; Ma, Y; Funahashi, N; Carraher, C; Brownell, Robert (2007)

    Journal article
    The University of Auckland Library

    Surveys of commercial markets combined with molecular taxonomy (i.e. molecular monitoring) provide a means to detect products from illegal, unregulated and/or unreported (IUU) exploitation, including the sale of fisheries bycatch and wild meat (bushmeat). Capture-recapture analyses of market products using DNA profiling have the potential to estimate the total number of individuals entering the market. However, these analyses are not directly analogous to those of living individuals because a ???market individual??? does not die suddenly but, instead, remains available for a time in decreasing quantities, rather like the exponential decay of a radioactive isotope. Here we use mitochondrial DNA (mtDNA) sequences and microsatellite genotypes to individually identify products from North Pacific minke whales ( Balaenoptera acutorostrata ssp.) purchased in 12 surveys of markets in the Republic of (South) Korea from 1999 to 2003. By applying a novel capture-recapture model with a decay rate parameter to the 205 unique DNA profiles found among 289 products, we estimated that the total number of whales entering trade across the five-year survey period was 827 (SE, 164; CV, 0.20) and that the average ???half-life??? of products from an individual whale on the market was 1.82 months (SE, 0.24; CV, 0.13). Our estimate of whales in trade (reflecting the true numbers killed) was significantly greater than the officially reported bycatch of 458 whales for this period. This unregulated exploitation has serious implications for the survival of this genetically distinct coastal population. Although our capture-recapture model was developed for specific application to the Korean whale-meat markets, the exponential decay function could be modified to improve the estimates of trade in other wildmeat or fisheries markets or abundance of living populations by noninvasive genotyping.

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  • Three Distinct Directions of Intramural Activation Reveal Non-uniform Side-to-side Electrical Coupling of Ventricular Myocytes

    Caldwell, B; Trew, Mark; Sands, Gregory; Le Grice, Ian; Smaill, Bruce; Hooks, Darren (2009)

    Journal article
    The University of Auckland Library

    Background??? The anisotropy of cardiac tissue is a key determinant of 3D electric propagation and the stability of activation wave fronts in the heart. The electric properties of ventricular myocardium are widely assumed to be axially anisotropic, with activation propagating most rapidly in the myofiber direction and at uniform velocity transverse to this. We present new experimental evidence that contradicts this view. Methods and Results??? For the first time, high-density intramural electric mapping (325 electrodes at ???4??4??1-mm spacing) from pig left ventricular tissue was used to reconstruct 3D paced activation surfaces projected directly onto 3D tissue structure imaged throughout the same left ventricular volume. These data from 5 hearts demonstrate that ventricular tissue is electrically orthotropic with 3 distinct propagation directions that coincide with local microstructural axes defined by the laminar arrangement of ventricular myocytes. The maximum conduction velocity of 0.67??0.019 ms???1 was aligned with the myofiber axis. However, transverse to this, the maximum conduction velocity was 0.30??0.010 ms???1, parallel to the myocyte layers and 0.17??0.004 ms???1 normal to them. These orthotropic conduction velocities give rise to preferential activation pathways across the left ventricular free wall that are not captured by structurally detailed computer models, which incorporate axially anisotropic electric properties. Conclusions??? Our findings suggest that current views on uniform side-to-side electric coupling in the heart need to be revised. In particular, nonuniform laminar myocardial architecture and associated electric orthotropy should be included in future models of initiation and maintenance of ventricular arrhythmia.

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