27,637 results for The University of Auckland Library

  • United Nations Convention on the Rights of Persons with Disabilities and its implications for compulsory treatment and mental health nursing

    O'Brien, Anthony; Thom, Katey (2014-06)

    Journal article
    The University of Auckland Library

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  • Synthesis and cytotoxicity of thieno[2,3-b]quinoline-2-carboxamide and cycloalkyl[b]thieno[3,2-e]pyridine-2-carboxamide derivatives

    Leung, Yee Fun; Pilkington, Lisa; van Rensburg, M; Jeon, CY; Song, M; Arabshahi, HJ; De Zoysa, Gayan; Sarojini Amma, Vijayalekshmi; Denny, William; Reynisson, Johannes; Barker, David (2016)

    Journal article
    The University of Auckland Library

    Seventy nine derivatives of thieno[2,3-b]quinolines, tetrahydrothieno[2,3-b]quinoline, dihydrocyclopenta[b]thieno[3,2-e]pyridine, cyclohepta[b]thieno[3,2-e]pyridine and hexahydrocycloocta[b]thieno[3,2-e]pyridine were either synthesized or obtained commercially and tested for their antiproliferative activity against HCT116, MDA-MB-468 and MDA-MB-231 human cancer cell lines. The most potent eight compounds were active against all cell lines with IC50 values in the 80-250nM range. In general hexahydrocycloocta[b]thieno[3,2-e]pyridines were most active with increasing activity observed as larger cycloalkyl rings were fused to the pyridine ring.

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  • Evidence of bias in assessment of fisheries management impacts

    Slooten, E; Simmons, Glenn; Dawson, SM; Bremner, G; Thrush, Simon; Whittaker, H; McCormack, F; Robertson, BC; Haworth, Nigel; Clarke, PJ; Pauly, D; Zeller, D (2017-06-20)

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    The University of Auckland Library

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  • Tramadol: Keep calm and carry on

    Anderson, Brian; Thomas, J; Ottaway, K; Chalkiadis, GA (2017-08)

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    The University of Auckland Library

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  • Acute rheumatic fever

    Webb, Rachel; Grant, Cameron; Harnden, A (2015-01)

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    The University of Auckland Library

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  • Pharmacokinetic and anti-cancer properties of high dose ascorbate in solid tumours of ascorbate-dependent mice

    Campbell, EJ; Vissers, MCM; Wohlrab, C; Hicks, Kevin; Strother, RM; Bozonet, SM; Robinson, BA; Dachs, Gabriele (2016-10)

    Journal article
    The University of Auckland Library

    Despite recent evidence for an anti-tumour role for high-dose ascorbate, potential mechanisms of action are still unclear. At mM concentrations that are achieved with high-dose intravenous administration, autoxidation of ascorbate can generate cytotoxic levels of H2O2. Ascorbate is also a required co-factor for the hydroxylases that suppress the transcription factor hypoxia-inducible factor (HIF-1). HIF-1 supports an aggressive tumour phenotype and is associated with poor prognosis, and previous studies have shown that optimizing intracellular ascorbate levels down-regulates HIF-1 activation. In this study we have simultaneously measured ascorbate concentrations and the HIF-1 pathway activity in tumour tissue following high dose ascorbate administration, and have studied tumour growth and physiology. Gulo-/- mice, a model of the human ascorbate dependency condition, were implanted with syngeneic Lewis lung tumours, 1g/kg ascorbate was administered into the peritoneum, and ascorbate concentrations were monitored in plasma, liver and tumours. Ascorbate levels peaked within 30min, and although plasma and liver ascorbate returned to baseline within 16h, tumour levels remained elevated for 48h, possibly reflecting increased stability in the hypoxic tumour environment. The expression of HIF-1 and its target proteins was down-regulated with tumour ascorbate uptake. Elevated tumour ascorbate levels could be maintained with daily administration, and HIF-1 and vascular endothelial growth factor protein levels were reduced in these conditions. Increased tumour ascorbate was associated with slowed tumour growth, reduced tumour microvessel density and decreased hypoxia. Alternate day administration of ascorbate resulted in lower tumour levels and did not consistently decrease HIF-1 pathway activity. Levels of sodium-dependent vitamin C transporters 1 and 2 were not clearly associated with ascorbate accumulation by murine tumour cells in vitro or in vivo. Our results support the suppression of the hypoxic response by ascorbate as a plausible mechanism of action of its anti-tumour activity, and this may be useful in a clinical setting.

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  • Survey of the bp/tee genes from clinical group A streptococcus isolates in New Zealand - implications for vaccine development

    Steemson, John; Moreland, Nicole; Williamson, D; Morgan, J; Carter, PE; Proft, Thomas (2014-12)

    Journal article
    The University of Auckland Library

    Group A streptococcus (GAS) is responsible for a wide range of diseases ranging from superficial infections, such as pharyngitis and impetigo, to life-threatening diseases, such as toxic shock syndrome and acute rheumatic fever (ARF). GAS pili are hair-like extensions protruding from the cell surface and consist of highly immunogenic structural proteins: the backbone pilin (BP) and one or two accessory pilins (AP1 and AP2). The protease-resistant BP builds the pilus shaft and has been recognized as the T-antigen, which forms the basis of a major serological typing scheme that is often used as a supplement to M typing. A previous sequence analysis of the bp gene (tee gene) in 39 GAS isolates revealed 15 different bp/tee types. In this study, we sequenced the bp/tee gene from 100 GAS isolates obtained from patients with pharyngitis, ARF or invasive disease in New Zealand. We found 20 new bp/tee alleles and four new bp/tee types/subtypes. No association between bp/tee type and clinical outcome was observed. We confirmed earlier reports that the emm type and tee type are associated strongly, but we also found exceptions, where multiple tee types could be found in certain M/emm type strains, such as M/emm89. We also reported, for the first time, the existence of a chimeric bp/tee allele, which was assigned into a new subclade (bp/tee3.1). A strong sequence conservation of the bp/tee gene was observed within the individual bp/tee types/subtypes (>97???% sequence identity), as well as between historical and contemporary New Zealand and international GAS strains. This temporal and geographical sequence stability provided further evidence for the potential use of the BP/T-antigen as a vaccine target.

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  • Connective Tissue Disease-associated Interstitial Lung Diseases (CTD-ILD) - Report from OMERACT CTD-ILD Working Group

    Khanna, D; Mittoo, S; Aggarwal, R; Proudman, SM; Dalbeth, Nicola; Matteson, EL; Brown, K; Flaherty, K; Wells, AU; Seibold, JR; Strand, V (2015-03)

    Journal article
    The University of Auckland Library

    OBJECTIVE: Interstitial lung disease (ILD) is common in connective tissue disease (CTD) and is the leading cause of mortality. Investigators have used certain outcome measures in randomized controlled trials (RCT) in CTD-ILD, but the lack of a systematically developed, CTD-specific index that captures all measures relevant and meaningful to patients with CTD-ILD has left a large and conspicuous gap in CTD-ILD research. METHODS: The CTD-ILD working group, under the aegis of the Outcome Measures in Rheumatology (OMERACT) initiative, has completed a consensus group exercise to reach harmony on core domains and items for inclusion in RCT in CTD-ILD. During the OMERACT 12 meeting, consensus was sought on domains and core items for inclusion in RCT. In addition, consensus was pursued on a definition of response in RCT. Consensus was defined as ??? 75% agreement among the participants. RESULTS: OMERACT 12 participants endorsed the domains with minimal modifications. Clinically meaningful progression for CTD-ILD was proposed as ??? 10% relative decline in forced vital capacity (FVC) or ??? 5% to < 10% relative decline in FVC and ??? 15% relative decline in DLCO. CONCLUSION: There is consensus on domains for inclusion in RCT in CTD-ILD and on a definition of clinically meaningful progression. Data-driven approaches to validate these results in different cohorts and RCT are needed.

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  • Robust Vehicle Detection and Distance Estimation Under Challenging Lighting Conditions

    Rezaei, Mahdi; Terauchi, M; Klette, M (2015-05)

    Journal article
    The University of Auckland Library

    Avoiding high computational costs and calibration issues involved in stereo-vision based algorithms, this article proposes real-time monocular-vision based techniques for simultaneous vehicle detection and inter-vehicle distance estimation, in which the performance and robustness of the system remain competitive, even for highly challenging benchmark datasets. The paper develops a collision warning system by detecting vehicles ahead, and by identifying safety distances to assist a distracted driver, prior to occurrence of an imminent crash. We introduce adaptive global Haar-like features for vehicle detection, tail-light segmentation, virtual symmetry detection, inter-vehicle distance estimation, as well as an efficient single-sensor multifeature fusion technique to enhance the accuracy and robustness of our algorithm. The proposed algorithm is able to detect vehicles ahead both at day or night, and also for short- and long-range distances. Experimental results under various weather and lighting conditions (including sunny, rainy, foggy, or snowy) show that the proposed algorithm outperforms state-of-the-art algorithms.

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  • Estimating Core Number in Assemblages: Core Movement and Mobility During the Holocene of the Fayum, Egypt

    Phillipps, Rebecca; Holdaway, Simon (2016-06)

    Journal article
    The University of Auckland Library

    The utility of the cortex ratio first developed by Dibble et al. (American Antiquity, 70(3), 545???560, 2005) and extended by Douglass et al. (American Antiquity, 73(3), 513???526, 2008) is examined in contexts where cores rather than flakes may be transported. The cortex ratio is used to demonstrate the movement of artifacts by quantifying missing surface area, typically where it is the flakes that were removed and the cores that were left behind. In such situations, the removal of flakes with small volumes will result in the removal of relatively large cortical surface areas resulting in a low cortex ratio. However, when it is the cores that were removed, assemblages will lose greater proportions of artifact volume relative to the loss of artifact surface area. Here, we propose methods to investigate the effects of high-volume artifact removal from archeological assemblages as a proxy for human movement in addition to the cortex ratio. We apply the methods to stone artifact assemblages from the Fayum, Egypt, where changes in mid-Holocene mobility are closely linked to food production.

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  • Characterization of tissue-specific differential DNA methylation suggests distinct modes of positive and negative gene expression regulation

    Wan, J; Oliver, Verity; Wang, G; Zhu, H; Zack, DJ; Merbs, SL; Qian, J (2015)

    Journal article
    The University of Auckland Library

    BACKGROUND: DNA methylation plays an important role in regulating gene expression during many biological processes. However, the mechanism of DNA-methylation-dependent gene regulation is not fully understood. Here, we explore two possible DNA methylation regulatory mechanisms with opposite modes of gene expression regulation. RESULTS: By comparing the genome-wide methylation and expression patterns in different tissues, we find that majority of tissue-specific differentially methylated regions (T-DMRs) are negatively correlated with expression of their associated genes (negative T-DMRs), consistent with the classical dogma that DNA methylation suppresses gene expression; however, a significant portion of T-DMRs are positively correlated with gene expression (positive T-DMRs). We observe that the positive T-DMRs have similar genomic location as negative T-DMRs, except that the positive T-DMRs are more enriched in the promoter regions. Both positive and negative T-DMRs are enriched in DNase I hypersensitivity sites (DHSs), suggesting that both are likely to be functional. The CpG sites of both positive and negative T-DMRs are also more evolutionarily conserved than the genomic background. Interestingly, the putative target genes of the positive T-DMR are enriched for negative regulators such as transcriptional repressors, suggesting a novel mode of indirect DNA methylation inhibition of expression through transcriptional repressors. Likewise, two distinct sets of DNA sequence motifs exist for positive and negative T-DMRs, suggesting that two distinct sets of transcription factors (TFs) are involved in positive and negative regulation mediated by DNA methylation. CONCLUSIONS: We find both negative and positive association between T-DMRs and gene expression, which implies the existence of two different mechanisms of DNA methylation-dependent gene regulation.

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  • Conditional knockdown of DNA methyltransferase 1 reveals a key role of retinal pigment epithelium integrity in photoreceptor outer segment morphogenesis

    Nasonkin, IO; Merbs, SL; Lazo, K; Oliver, Verity; Brooks, M; Patel, K; Enke, RA; Nellissery, J; Jamrich, M; Le, YZ; Bharti, K; Fariss, RN; Rachel, RA; Zack, DJ; Rodriguez-Boulan, EJ; Swaroop, A (2013-03-15)

    Journal article
    The University of Auckland Library

    Dysfunction or death of photoreceptors is the primary cause of vision loss in retinal and macular degenerative diseases. As photoreceptors have an intimate relationship with the retinal pigment epithelium (RPE) for exchange of macromolecules, removal of shed membrane discs and retinoid recycling, an improved understanding of the development of the photoreceptor-RPE complex will allow better design of gene- and cell-based therapies. To explore the epigenetic contribution to retinal development we generated conditional knockout alleles of DNA methyltransferase 1 (Dnmt1) in mice. Conditional Dnmt1 knockdown in early eye development mediated by Rx-Cre did not produce lamination or cell fate defects, except in cones; however, the photoreceptors completely lacked outer segments despite near normal expression of phototransduction and cilia genes. We also identified disruption of RPE morphology and polarization as early as E15.5. Defects in outer segment biogenesis were evident with Dnmt1 exon excision only in RPE, but not when excision was directed exclusively to photoreceptors. We detected a reduction in DNA methylation of LINE1 elements (a measure of global DNA methylation) in developing mutant RPE as compared with neural retina, and of Tuba3a, which exhibited dramatically increased expression in mutant retina. These results demonstrate a unique function of DNMT1-mediated DNA methylation in controlling RPE apicobasal polarity and neural retina differentiation. We also establish a model to study the epigenetic mechanisms and signaling pathways that guide the modulation of photoreceptor outer segment morphogenesis by RPE during retinal development and disease.

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  • Sustainable development and the water???energy???food nexus: a perspective on livelihoods

    Biggs, EM; Bruce, E; Boruff, B; Duncan, JMA; Horsley, J; Pauli, N; McNeill, Kellie; Neef, Andreas; Van Ogtrop, F; Curnow, J; Haworth, B; Duce, S; Imanari, Y (2015)

    Journal article
    The University of Auckland Library

    The water???energy???food nexus is being promoted as a conceptual tool for achieving sustainable development. Frameworks for implementing nexus thinking, however, have failed to explicitly or adequately incorporate sustainable livelihoods perspectives. This is counterintuitive given that livelihoods are key to achieving sustainable development. In this paper we present a critical review of nexus approaches and identify potential linkages with sustainable livelihoods theory and practice, to deepen our understanding of the interrelated dynamics between human populations and the natural environment. Building upon this review, we explore the concept of ???environmental livelihood security??? ??? which encompasses a balance between natural resource supply and human demand on the environment to promote sustainability ??? and develop an integrated nexus-livelihoods framework for examining the environmental livelihood security of a system. The outcome is an integrated framework with the capacity to measure and monitor environmental livelihood security of whole systems by accounting for the water, energy and food requisites for livelihoods at multiple spatial scales and institutional levels. We anticipate this holistic approach will not only provide a significant contribution to achieving national and regional sustainable development targets, but will also be effective for promoting equity amongst individuals and communities in local and global development agendas.

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  • STroke imAging pRevention and treatment (START): A longitudinal stroke cohort study: Clinical trials protocol

    Carey, LM; Crewther, S; Salvado, O; Lind??n, T; Connelly, A; Wilson, W; Howells, DW; Churilov, L; Ma, H; Tse, T; Rose, S; Palmer, S; Bougeat, P; Campbell, BC; Christensen, S; Macaulay, SL; Favaloro, J; O' Collins, V; McBride, S; Bates, S; Cowley, E; Dewey, H; Wijeratne, T; Gerraty, R; Phan, TG; Yan, B; Parsons, MW; Bladin, C; Barber, Peter; Read, S; Wong, A; Lee, A; Kleinig, T; Hankey, GJ; Blacker, D; Markus, R; Leyden, J; Krause, M; Grimley, R; Mahant, N; Jannes, J; Sturm, J; Davis, SM; Donnan, GA; START Research Team (2015-06)

    Journal article
    The University of Auckland Library

    RATIONALE: Stroke and poststroke depression are common and have a profound and ongoing impact on an individual's quality of life. However, reliable biological correlates of poststroke depression and functional outcome have not been well established in humans. AIMS: Our aim is to identify biological factors, molecular and imaging, associated with poststroke depression and recovery that may be used to guide more targeted interventions. DESIGN: In a longitudinal cohort study of 200 stroke survivors, the START-STroke imAging pRevention and Treatment cohort, we will examine the relationship between gene expression, regulator proteins, depression, and functional outcome. Stroke survivors will be investigated at baseline, 24???h, three-days, three-months, and 12 months poststroke for blood-based biological associates and at days 3-7, three-months, and 12 months for depression and functional outcomes. A sub-group (n???=???100), the PrePARE: Prediction and Prevention to Achieve optimal Recovery Endpoints after stroke cohort, will also be investigated for functional and structural changes in putative depression-related brain networks and for additional cognition and activity participation outcomes. Stroke severity, diet, and lifestyle factors that may influence depression will be monitored. The impact of depression on stroke outcomes and participation in previous life activities will be quantified. STUDY OUTCOMES: Clinical significance lies in the identification of biological factors associated with functional outcome to guide prevention and inform personalized and targeted treatments. Evidence of associations between depression, gene expression and regulator proteins, functional and structural brain changes, lifestyle and functional outcome will provide new insights for mechanism-based models of poststroke depression.

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  • The perception of real and illusory motion in schizophrenia

    Crawford, TJ; Hamm, Jeffrey; Kean, M; Schmechtig, A; Kumari, V; Anilkumar, AP; Ettinger, U (2010-08)

    Journal article
    The University of Auckland Library

    An illusion of rapid movement is normally perceived when an attentional cue (such as a peripheral flash) preceeds the onset of a line. The movement is perceived as receding away from the cue. This study investigated how this illusion was perceived by people with schizophrenia. Nineteen participants with schizophrenia and 26 healthy matched controls were presented with a series of real, illusory, no motion or combined real and illusory motion stimuli at various target speeds. Detection thresholds were measured to determine the reliability of motion perception. The participants with schizophrenia were not distinguished from the control group in the perception of real motion. However, the motion detection curves for the schizophrenia group revealed a reduction in the perceptual effect of illusory motion in comparison to controls. The findings revealed that people with schizophrenia may be less easily deceived by illusory motion in comparison to healthy participants.

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  • Endovascular Therapy for Ischemic Stroke with Perfusion-Imaging Selection

    Campbell, BCV; Mitchell, PJ; Kleinig, TJ; Dewey, HM; Churilov, L; Yassi, N; Yan, B; Dowling, RJ; Parsons, MW; Oxley, TJ; Wu, TY; Brooks, M; Simpson, MA; Miteff, F; Levi, CR; Krause, M; Harrington, TJ; Faulder, KC; Steinfort, BS; Priglinger, M; Ang, T; Scroop, R; Barber, Peter; McGuinness, B; Wijeratne, T; Phan, TG; Chong, W; Chandra, RV; Bladin, CF; Badve, M; Rice, H; de Villiers, L; Ma, H; Desmond, PM; Donnan, GA; Davis, SM (2015-03-12)

    Journal article
    The University of Auckland Library

    Background Trials of endovascular therapy for ischemic stroke have produced variable results. We conducted this study to test whether more advanced imaging selection, recently developed devices, and earlier intervention improve outcomes. Methods We randomly assigned patients with ischemic stroke who were receiving 0.9 mg of alteplase per kilogram of body weight less than 4.5 hours after the onset of ischemic stroke either to undergo endovascular thrombectomy with the Solitaire FR (Flow Restoration) stent retriever or to continue receiving alteplase alone. All the patients had occlusion of the internal carotid or middle cerebral artery and evidence of salvageable brain tissue and ischemic core of less than 70 ml on computed tomographic (CT) perfusion imaging. The coprimary outcomes were reperfusion at 24 hours and early neurologic improvement (???8-point reduction on the National Institutes of Health Stroke Scale or a score of 0 or 1 at day 3). Secondary outcomes included the functional score on the modified Rankin scale at 90 days. Results The trial was stopped early because of efficacy after 70 patients had undergone randomization (35 patients in each group). The percentage of ischemic territory that had undergone reperfusion at 24 hours was greater in the endovascular-therapy group than in the alteplase-only group (median, 100% vs. 37%; P<0.001). Endovascular therapy, initiated at a median of 210 minutes after the onset of stroke, increased early neurologic improvement at 3 days (80% vs. 37%, P=0.002) and improved the functional outcome at 90 days, with more patients achieving functional independence (score of 0 to 2 on the modified Rankin scale, 71% vs. 40%; P=0.01). There were no significant differences in rates of death or symptomatic intracerebral hemorrhage. Conclusions In patients with ischemic stroke with a proximal cerebral arterial occlusion and salvageable tissue on CT perfusion imaging, early thrombectomy with the Solitaire FR stent retriever, as compared with alteplase alone, improved reperfusion, early neurologic recovery, and functional outcome. (Funded by the Australian National Health and Medical Research Council and others; EXTEND-IA ClinicalTrials.gov number, NCT01492725, and Australian New Zealand Clinical Trials Registry number, ACTRN12611000969965.)

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  • It is not just muscle mass: a review of muscle quality, composition and metabolism during ageing as determinants of muscle function and mobility in later life

    McGregor, Robin; Cameron-Smith, David; Poppitt, Sally (2014-01)

    Journal article
    The University of Auckland Library

    Worldwide estimates predict 2 billion people will be aged over 65??years by 2050. A major current challenge is maintaining mobility and quality of life into old age. Impaired mobility is often a precursor of functional decline, disability and loss of independence. Sarcopenia which represents the age-related decline in muscle mass is a well-established factor associated with mobility limitations in older adults. However, there is now evidence that not only changes in muscle mass but other factors underpinning muscle quality including composition, metabolism, aerobic capacity, insulin resistance, fat infiltration, fibrosis and neural activation may also play a role in the decline in muscle function and impaired mobility associated with ageing. Importantly, changes in muscle quality may precede loss of muscle mass and therefore provide new opportunities for the assessment of muscle quality particularly in middle-aged adults who could benefit from interventions to improve muscle function. This review will discuss the accumulating evidence that in addition to muscle mass, factors underpinning muscle quality influence muscle function and mobility with age. Further development of tools to assess muscle quality in community settings is needed. Preventative diet, exercise or treatment interventions particularly in middle-aged adults at the low end of the spectrum of muscle function may help preserve mobility in later years and improve healthspan.

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  • Sports-related brain injury in the general population: An epidemiological study

    Theadom, Alice; Starkey, NJ; Dowell, T; Hume, PA; Kahan, M; McPherson, K; Feigin, V; Barker-Collo, Suzanne; Kydd, R; Parag, V; Brown, P; Ameratunga, Shanthi; Christey, G; Jones, K; Jones, A; Hardaker, N; Te Ao, Braden (2014-11)

    Journal article
    The University of Auckland Library

    Objectives: To determine the incidence, nature and severity of all sports-related brain injuries in the general population. Design: Population-based epidemiological incidence study. Methods: Data on all traumatic brain injury events sustained during a sports-related activity were extracted from a dataset of all new traumatic brain injury cases (both fatal and non-fatal), identified over a one-year period in the Hamilton and Waikato districts of New Zealand. Prospective and retrospective case ascertainment methods from multiple sources were used. All age groups and levels of traumatic brain injury severity were included. Details of the registering injuries and recurrent injuries sustained over the subsequent year were obtained through medical/accident records and assessment interviews with participants. Results: Of 1369 incident traumatic brain injury cases, 291 were identified as being sustained during a sports-related activity (21% of all traumatic brain injuries) equating to an incidence rate of 170 per 100,000 of the general population. Recurrent injuries occurred more frequently in adults (11%) than children (5%). Of the sports-related injuries 46% were classified as mild with a high risk of complications. Injuries were most frequently sustained during rugby, cycling and equestrian activities. It was revealed that up to 19% of traumatic brain injuries were not recorded in medical notes. Conclusions: Given the high incidence of new and recurrent traumatic brain injury and the high risk of complications following injury, further sport specific injury prevention strategies are urgently needed to reduce the impact of traumatic brain injury and facilitate safer engagement in sports activities. The high levels of ???missed??? traumatic brain injuries, highlights the importance in raising awareness of traumatic brain injury during sports-related activity in the general population.

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  • Proportional recovery after stroke depends on corticomotor integrity

    Byblow, Winston; Stinear, Cathy; Barber, Peter; Petoe, MA; Ackerley, Suzanne (2015-12)

    Journal article
    The University of Auckland Library

    Objective: For most patients, resolution of upper limb impairment during the first 6 months poststroke is 70% of the maximum possible. We sought to identify candidate mechanisms of this proportional recovery. We hypothesized that proportional resolution of upper limb impairment depends on ipsilesional corticomotor pathway function, is mirrored by proportional recovery of excitability in this pathway, and is unaffected by upper limb therapy dose. Methods: Upper limb impairment was measured in 93 patients at 2, 6, 12, and 26 weeks after first-ever ischemic stroke. Motor evoked potentials (MEPs) and motor threshold were recorded from extensor carpi radialis using transcranial magnetic stimulation, and fractional anisotropy (FA) in the posterior limbs of the internal capsules was determined with diffusion-weighted magnetic resonance imaging. Results: Initial impairment score, presence of MEPs and FA asymmetry were the only predictors of impairment resolution, indicating a key role for corticomotor tract function. By 12 weeks, upper limb impairment resolved by 70% in patients with MEPs regardless of their initial impairment, and ipsilesional rest motor threshold also resolved by 70%. Resolution of impairment was insensitive to upper limb therapy dose. Interpretation: These findings indicate that upper limb impairment resolves by 70% of the maximum possible, regardless of initial impairment, but only for patients with intact corticomotor function. Impairment resolution seems to reflect spontaneous neurobiological processes that involve the ipsilesional corticomotor pathway. A better understanding of these mechanisms could lead to interventions that increase resolution of impairment above 70%.

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  • Improving Adherence to Secondary Stroke Prevention Strategies Through Motivational Interviewing: Randomized Controlled Trial

    Barker-Collo, Suzanne; Krishnamurthi, R; Witt, E; Feigin, V; Jones, A; Mcpherson, K; Starkey, N; Parag, Varsha; Jiang, Yannan; Barber, Peter; Rush, E; Bennett, D; Aroll, B (2015-12)

    Journal article
    The University of Auckland Library

    Background and Purpose???Stroke recurrence rates are high (20%???25%) and have not declined over past 3 decades. This study tested effectiveness of motivational interviewing (MI) for reducing stroke recurrence, measured by improving adherence to recommended medication and lifestyle changes compared with usual care. Methods???Single-blind, prospective phase III randomized controlled trial of 386 people with stroke assigned to either MI treatment (4 sessions at 28 days, 3, 6, and 9 months post stroke) or usual care; with outcomes assessed at 28 days, 3, 6, 9, and 12 months post stroke. Primary outcomes were change in systolic blood pressure and low-density lipoprotein cholesterol levels as indicators of adherence at 12 months. Secondary outcomes included self-reported adherence, new stroke, or coronary heart disease events (both fatal and nonfatal); quality of life (Short Form-36); and mood (Hospital Anxiety and Depression Scale). Results???MI did not significantly change measures of blood pressure (mean difference in change, ???0.2.35 [95% confidence interval, ???6.16 to 1.47]) or cholesterol (mean difference in change, ???0.0.12 [95% confidence interval, ???0.30 to 0.06]). However, it had positive effects on self-reported medication adherence at 6 months (1.979; 95% confidence interval, 0.98???3.98; P=0.0557) and 9 months (4.295; 95% confidence interval, 1.56???11.84; P=0.0049) post stroke. Improvement across other measures was also observed, but the differences between MI and usual care groups were not statistically significant. Conclusions???MI improved self-reported medication adherence. All other effects were nonsignificant, though in the direction of a treatment effect. Further study is required to determine whether MI leads to improvement in other important areas of functioning (eg, caregiver burden).

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