24,386 results for Journal article

  • A reduction of mitochondrial DNA molecules during embryogenesis explains the rapid segregation of genotypes.

    Cree, Lynsey; Samuels, DC; de Sousa Lopes, SC; Rajasimha, HK; Wonnapinij, P; Mann, JR; Dahl, HH; Chinnery, PF (2008-02)

    Journal article
    The University of Auckland Library

    Mammalian mitochondrial DNA (mtDNA) is inherited principally down the maternal line, but the mechanisms involved are not fully understood. Females harboring a mixture of mutant and wild-type mtDNA (heteroplasmy) transmit a varying proportion of mutant mtDNA to their offspring. In humans with mtDNA disorders, the proportion of mutated mtDNA inherited from the mother correlates with disease severity. Rapid changes in allele frequency can occur in a single generation. This could be due to a marked reduction in the number of mtDNA molecules being transmitted from mother to offspring (the mitochondrial genetic bottleneck), to the partitioning of mtDNA into homoplasmic segregating units, or to the selection of a group of mtDNA molecules to re-populate the next generation. Here we show that the partitioning of mtDNA molecules into different cells before and after implantation, followed by the segregation of replicating mtDNA between proliferating primordial germ cells, is responsible for the different levels of heteroplasmy seen in the offspring of heteroplasmic female mice.

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  • The phenotype of limb-girdle muscular dystrophy type 2I.

    Poppe, M; Cree, Lynsey; Bourke, J; Eagle, M; Anderson, LV; Birchall, D; Brockington, M; Buddles, M; Busby, M; Muntoni, F; Wills, A; Bushby, K (2003-04-22)

    Journal article
    The University of Auckland Library

    Mutations in the fukutin-related protein gene FKRP cause limb-girdle muscular dystrophy (LGMD2I) as well as a form of congenital muscular dystrophy (MDC1C). Background : Mutations in the fukutin-related protein gene FKRP cause limb-girdle muscular dystrophy (LGMD2I) as well as a form of congenital muscular dystrophy (MDC1C). Objective : To define the phenotype in LGMD2I. Methods : The authors assessed 16 patients from 14 families with FKRP gene mutations and LGMD and collected the results of mutation analysis, protein studies, and respiratory and cardiac investigations. Results : Thirteen patients, most with adult presentation, were homozygous for the common C826A mutation in FKRP. The three other cases were compound heterozygotes for C826A and two of them presented in childhood, with more progressive disease. The pattern of muscle involvement, frequently including calf hypertrophy, was similar to dystrophinopathy. Complications in patients with LGMD2I were common and sometimes out of proportion to the skeletal muscle involvement. Six patients had cardiac involvement, and 10 had respiratory impairment: five required nocturnal respiratory support. All patients had serum creatine kinase at least 5 to 70 times normal. The most consistent protein abnormality found on muscle biopsy was a reduction of laminin [alpha]2 immunolabeling, either on muscle sections or immunoblotting alone. Conclusions : LGMD2I due to FKRP mutations appears to be a relatively common cause of LGMD, with respiratory and cardiac failure as prominent complications.

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  • Synthetic routes to mixed-ligand cobalt(III) dithiocarbamato complexes containing imidazole, amine and pyridine donors and the X-ray crystal structure of a cobalt(III) bis(dithiocarbamato) histamine complex.

    Hodgson, MC; Brothers, Penelope; Clark, George; Ware, David (2008)

    Journal article
    The University of Auckland Library

    The binuclear cobalt complex [Co2(Me2dtc)5]+ reacts with a range of nitrogen donor ligands L??? or L??? to form an equimolar mixture of Co(Me2dtc)3 and the mixed-ligand complexes [Co(Me2dtc)2(L???)2]+ or [Co(Me2dtc)2(L???)]+, where (L???)2 is two monodentate ligands and (L???) is one bidentate ligand. The complexes prepared by this route contain the monodentate ligands L??? = 1-methyl-imidazole, 1-methyl-5-nitro-imidazole and benzimidazole, all of which coordinate to cobalt through an imidazole nitrogen atom. Symmetrical bidentate ligand complexes contain the bisimidazole L??? = 2,2???-bis(4,5-dimethylimidazole), the diamine L??? = 1,2-diaminobenzene and the pyridine donors L??? = 2,2???-bipyridine, 4,4???-dimethyl-2,2???-bipyridine and 1,10-phenanthroline. Two examples of complexes with unsymmetrical bidentate imidazole-amine donors were prepared in which L??? = 4-(2-aminoethyl)imidazole (histamine) and 2-aminomethylbenzimidazole. All new complexes were fully characterised, and the X-ray crystal structure of the histamine complex [Co(Me2dtc)2(hist)]ClO4 is also reported.

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  • Differential Localization of gamma-Aminobutyric Acid Type A and Glycine Receptor Subunits and Gephyrin in the Human Pons, Medulla Oblongata and Uppermost Cervical Segment of the Spinal Cord: An Immunohistochemical Study

    Waldvogel, Henry; Baer, K; Eady, E; Allen, Kathryn; Gilbert, Raymond; Mohler, Hans; Rees, Mark; Nicholson, Louise; Faull, Richard (2010-02-01)

    Journal article
    The University of Auckland Library

    Gephyrin is a multifunctional protein responsible for the clustering of glycine receptors (GlyR) and gamma-aminobutyric acid type A receptors (GABA(A)R). GlyR and GABA(A)R are heteropentameric chloride ion channels that facilitate fast-response, inhibitory neurotransmission in the mammalian brain and spinal cord. We investigated the immunohistochemical distribution of gephyrin and the major GABA(A)R and GlyR subunits in the human light microscopically in the rostral and caudal one-thirds of the pons, in the middle and caudal one-thirds of the medulla oblongata, and in the first cervical segment of the spinal cord. The results demonstrate a widespread pattern of immunoreactivity for GlyR and GABA(A)R subunits throughout these regions, including the spinal trigeminal nucleus, abducens nucleus, facial nucleus, pontine reticular formation, dorsal motor nucleus of the vagus nerve, hypoglossal nucleus, lateral cuneate nucleus, and nucleus of the solitary tract. The GABA(A)R alpha(1), and GlyR alpha(1), and beta subunits show high levels of immunoreactivity in these nuclei. The GABA(A)R subunits alpha(2), alpha(3), beta(2,3), and gamma(2) present weaker levels of immunoreactivity. Exceptions are intense levels of GABA(A)R alpha(2) subunit immunoreactivity in the inferior olivary complex and high levels of GABA(A)R alpha(3) subunit immunoreactivity in the locus coeruleus and raphe nuclei. Gephyrin immunoreactivity is highest in the first segment of the cervical spinal cord and hypoglossal nucleus. Our results suggest that a variety of different inhibitory receptor subtypes is responsible for inhibitory functions in the human brainstem and cervical spinal cord and that gephyrin functions as a clustering molecule for major subtypes of these inhibitory neurotransmitter receptors. J. Comp. Neurol. 518:305-328, 2010. (C) 2009 Wiley-Liss, Inc.

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  • The synthesis and biological evaluation of novel series of nitrile-containing fluoroquinolones as antibacterial agents

    Murphy, ST; Case, HL; Ellsworth, E; Hagen, S; Huband, M; Joannides, T; Limberakis, C; Marotti, KR; Ottolini, AM; Rauckhorst, M; Starr, J; Stier, M; Taylor, C; Zhu, T; Blaser, Adrian; Denny, William; Lu, Guo-Liang; Smaill, Jeffrey; Rivault, Freddy (2007)

    Journal article
    The University of Auckland Library

    Several novel series of nitrile-containing fluoroquinolones with weakly basic amines are reported which have reduced potential for hERG (human ether-a-go-go gene) channel inhibition as measured by the dofetilide assay. The new fluoroquinolones are potent against both Gram-positive and fastidious Gram-negative strains, including Methicillin resistant Staphylococcus aureus and fluoroquinolone-resistant Streptococcus pneumoniae. Several analogs also showed low potential for human genotoxicity as measured by the clonogenicity test. Compounds 22 and 37 (designated PF-00951966 and PF-02298732, respectively), which had good in vitro activity and in vitro safety profiles, also showed good pharmacokinetic properties in rats.

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  • Fitting regression models with response-biased samples

    Scott, Alastair; Wild, Christopher (2011-09)

    Journal article
    The University of Auckland Library

    This paper extends the work in Lawless, Kalbfleisch, & Wild (1999) on fitting regression models with response-biased samples, that is, samples where some or all the covariates are missing for some units and the probability that this happens depends in part on the value of the reponse of that unit. In general, the resulting likelihood depends on the distribution of the covariates but we are only interested in methods that do not involve modelling this distribution. We look at a variety of methods based on estimating equations, at the relationship of these methods to semi-parametric efficient methods in cases where such methods exist, and show ways of obtaining efficiency gains that can sometimes be dramatic. The Canadian Journal of Statistics 39: 519???536; 2011 ?? 2011 Statistical Society of Canada Cet article g??n??ralise les travaux de Lawless, Kalbfleisch et Wild (1999) sur l'ajustement de mod??les de r??gression pour des ??chantillons avec biais d?? a la r??ponse, c'est-??-dire des ??chantillons pour lesquels quelques ou toutes les covariables sont manquantes pour quelques unites et la probabilit?? que cela se produise d??pend de la valeur de la variable r??ponse de ces unit??s. En g??n??ral, la vraisemblance r??sultante depend de la distribution des covariables, mais nous sommes uniquement int??ress??s aux m??thodes qui n'impliquent pas la mod??lisation de cette distribution. Nous consid??rons une vari??t?? de m??thodes bas??es sur les ??quations d'estimation et ?? la relation entre ces m??thodes et les m??thodes semi-param??triques efficaces lorsque celles-ci existent. Nous montrons des fa??ons d'obtenir des gains d'efficacit?? qui peuvent parfois ??tre tr??s importants. La revue canadienne de statistique 39:519???536;2011 ?? 2011 Soci??t?? statistique du Canada

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  • The Digby Mary Magdalen: Constructing the apostola apostalorum

    Carter, Susan (2009)

    Journal article
    The University of Auckland Library

    The Digby play, performed in a period when women were excluded from preaching, celebrates Mary Magdalene as a most successful preacher. 2 It is not a marginal work: this is a large play which takes over three hours to perform, has a cast of over 60, and thus would need at least 100 people to produce. 3 The play is highly entertaining, with stage mechanics, song, and dangerous-sounding pyrotechnics. With impressive spectacle the play shows the Magdalene as the apostola apostolorum: a woman who out-apostles the apostles. 4 There is a challenging irony in the situation of a woman preaching before a medieval audience, as Theresa Coletti shows and investigates. Coletti, noting that "discourses of female vice and virtue are deeply implicated in visions of social order, hierarchy, and control," 5 examines the historical East Anglian context of the Digby Mary Magdalen more fully in her book, Mary Magdalene and the Drama of Saints. I want to add to Coletti's anatomization of the play further evidence of its feminine perspective. Agreeing that "Medieval dramatic performance can no longer be construed as unreflective vehicles of instruction in a timeless Christian faith," 6 I examine the way that the Digby play heightens Magdalene's transgression of gender roles. In line with non-biblical material it amalgamates several episodes now considered not to belong to the Magdalene but to other women. 7 Consistently, dramatic strategies endorse the Magdalene's social transgressions: her open sexuality and her preaching. There are male foils to female

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  • Spectroscopic and computational study of ??-ethynylphenylene substituted zinc and free-base porphyrins

    Earles, JC; Gordon, KC; Stephenson, AWI; Partridge, Ashton; Officer, DL (2011)

    Journal article
    The University of Auckland Library

    A series of tetraphenylporphyrins appended at the b-pyrrolic position with an ethynylphenyleneor ethynylpyridine-substituent have been subjected to spectroscopic and density functional theory (DFT) analyses. The mean absolute deviation between corresponding experimental and DFT-derived vibrational spectra is up to 10.2 cm 1 , suggesting that the DFT B3LYP/6-31G(d) method provides an accurate model of the b-substituted porphyrin systems. The con???guration interactions that give rise to prominent electronic absorptions have been calculated using time-dependant DFT (TD-DFT) and have been rationalized with reference to the energy and topology of DFT calculated molecular orbitals. As the electron withdrawing capacity of the b-substituent increases the LUMO orbital gains appreciable amplitude over the substituent moiety and is stabilised. This represents a departure from the assumptions underpinning the Gouterman four-orbital model, resulting in atypical electronic absorption spectra. This phenomenon is also manifested in the enhancement patterns of the resonance Raman spectra insofar as B-band excitation engenders an enhancement of substituent based modes. These observations demonstrate that the b-substituent exerts an appreciable electronic in???uence on the porphyrin p-electron system and provides a means of introducing charge-transfer character to prominent electronic transitions.

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  • Analysis of individual molecular events of DNA damage response by flow- and image-assisted cytometry.

    Darzynkiewicz, Z; Traganos, F; Zhao, H; Halicka, HD; Skommer, Joanna; Wlodkowic, Donald (2011)

    Journal article
    The University of Auckland Library

    This chapter describes molecular mechanisms of DNA damage response (DDR) and presents flow- and image-assisted cytometric approaches to assess these mechanisms and measure the extent of DDR in individual cells. DNA damage was induced by cell treatment with oxidizing agents, UV light, DNA topoisomerase I or II inhibitors, cisplatin, tobacco smoke, and by exogenous and endogenous oxidants. Chromatin relaxation (decondensation) is an early event of DDR chromatin that involves modification of high mobility group proteins (HMGs) and histone H1 and was detected by cytometry by analysis of the susceptibility of DNA in situ to denaturation using the metachromatic fluorochrome acridine orange. Translocation of the MRN complex consisting of Meiotic Recombination 11 Homolog A (Mre11), Rad50 homolog, and Nijmegen Breakage Syndrome 1 (NMR1) into DNA damage sites was assessed by laser scanning cytometry as the increase in the intensity of maximal pixel as well as integral value of Mre11 immunofluorescence. Examples of cytometric detection of activation of Ataxia telangiectasia mutated (ATM), and Check 2 (Chk2) protein kinases using phospho-specific Abs targeting Ser1981 and Thr68 of these proteins, respectively are also presented. We also discuss approaches to correlate activation of ATM and Chk2 with phosphorylation of p53 on Ser15 and histone H2AX on Ser139 as well as with cell cycle position and DNA replication. The capability of laser scanning cytometry to quantify individual foci of phosphorylated H2AX and/or ATM that provides more dependable assessment of the presence of DNA double-strand breaks is outlined. The new microfluidic Lab-on-a-Chip platforms for interrogation of individual cells offer a novel approach for DDR cytometric analysis.

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  • Dynamic analysis of apoptosis using cyanine SYTO probes: from classical to microfluidic cytometry.

    Wlodkowic, Donald; Skommer, Joanna; Faley, S; Darzynkiewicz, Z; Cooper, JM (2009-06-10)

    Journal article
    The University of Auckland Library

    Cell death is a stochastic process, often initiated and/or executed in a multi-pathway/multi-organelle fashion. Therefore, high-throughput single-cell analysis platforms are required to provide detailed characterization of kinetics and mechanisms of cell death in heterogeneous cell populations. However, there is still a largely unmet need for inert fluorescent probes, suitable for prolonged kinetic studies. Here, we compare the use of innovative adaptation of unsymmetrical SYTO dyes for dynamic real-time analysis of apoptosis in conventional as well as microfluidic chip-based systems. We show that cyanine SYTO probes allow non-invasive tracking of intracellular events over extended time. Easy handling and "stain-no wash" protocols open up new opportunities for high-throughput analysis and live-cell sorting. Furthermore, SYTO probes are easily adaptable for detection of cell death using automated microfluidic chip-based cytometry. Overall, the combined use of SYTO probes and state-of-the-art Lab-on-a-Chip platform emerges as a cost effective solution for automated drug screening compared to conventional Annexin V or TUNEL assays. In particular, it should allow for dynamic analysis of samples where low cell number has so far been an obstacle, e.g. primary cancer stems cells or circulating minimal residual tumors.

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  • Audit of short term outcomes of surgical and medical second trimester termination of pregnancy.

    Mauelshagen, A; Sadler, Lynn; Roberts, Helen; Harilall, Mahesh; Farquhar, Cynthia (2009)

    Journal article
    The University of Auckland Library

    Background: As comparisons of modern medical and surgical second trimester termination of pregnancy (TOP) are limited, and the optimum method of termination is still debated, an audit of second trimester TOP was undertaken, with the objective of comparing the outcomes of modern medical and surgical methods. Methods: All cases of medical and surgical TOP between the gestations of 13 and 20 weeks from 1st January 2007 to 30th June 2008, among women residing in the local health board district, a tertiary teaching hospital in an urban setting, were identified by a search of ICD-10 procedure codes (surgical terminations) and from a ward database (medical terminations). Retrospective review of case notes was undertaken. A total of 184 cases, 51 medical and 133 surgical TOP, were identified. Frequency data were compared using Chi-squared or Fischer's Exact tests as appropriate and continuous data are presented as mean and standard deviation if normally distributed or median and interquartile range if non-parametric. Results: Eighty-one percent of surgical terminations occurred between 13 to 16 weeks gestation, while 74% of medical terminations were performed between 17 to 20 weeks gestation. The earlier surgical TOP occurred in younger women and were more often indicated for maternal mental health. Sixteen percent of medical TOP required surgical delivery of the placenta. Evacuation of retained products was required more often after medical TOP (10%) than after surgical TOP (1%). Other serious complications were rare. Conclusion: Both medical and surgical TOP are safe and effective for second trimester termination. Medical TOP tend to be performed at later gestations and are associated with a greater likelihood of manual removal of the placenta and delayed return to theatre for retained products. This case series does not address long term complications.

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  • Hormone therapy in postmenopausal women and risk of endometrial hyperplasia (updated).

    Furness, Susan; Roberts, Helen; Majoribanks, J; Lethaby, Elizabeth; Hickey, M; Farquhar, Cynthia (2009)

    Journal article
    The University of Auckland Library

    Background Declining circulating estrogen levels around the time of the menopause can induce unacceptable symptoms that affect the health and well being of women. Hormone therapy (both unopposed estrogen and estrogen/progestogen combinations) is an effective treatment for these symptoms, but is associated with risk of harms. Guidelines recommend that hormone therapy be given at the lowest effective dose and treatment should be reviewed regularly. The aim of this review is to identify the minimum dose(s) of progestogen required to be added to estrogen so that the rate of endometrial hyperplasia is not increased compared to placebo. Objectives The objective of this review is to assess which hormone therapy regimens provide effective protection against the development of endometrial hyperplasia and/or carcinoma. Search strategy We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched January 2008), The Cochrane Library (Issue 1, 2008), MEDLINE (1966 to May 2008), EMBASE (1980 to May 2008), Current Contents (1993 to May 2008), Biological Abstracts (1969 to 2008), Social Sciences Index (1980 to May 2008), PsycINFO (1972 to May 2008) and CINAHL (1982 to May 2008). Attempts were made to identify trials from citation lists of reviews and studies retrieved, and drug companies were contacted for unpublished data. Selection criteria Randomised comparisons of unopposed estrogen therapy, combined continuous estrogen-progestogen therapy and/or sequential estrogen-progestogen therapy with each other or placebo, administered over a minimum period of twelve months. Incidence of endometrial hyperplasia/carcinoma assessed by a biopsy at the end of treatment was a required outcome. Data on adherence to therapy, rates of additional interventions, and withdrawals due to adverse events were also extracted. Data collection and analysis In this substantive update, forty five studies were included. Odds ratios were calculated for dichotomous outcomes. The small numbers of studies in each comparison and the clinical heterogeneity precluded meta analysis for many outcomes. Main results Unopposed estrogen is associated with increased risk of endometrial hyperplasia at all doses, and durations of therapy between one and three years. For women with a uterus the risk of endometrial hyperplasia with hormone therapy comprising low dose estrogen continuously combined with a minimum of 1 mg norethisterone acetate or 1.5 mg medroxyprogesterone acetate is not significantly different from placebo (1mg NETA: OR=0.04 (0 to 2.8); 1.5mg MPA: no hyperplasia events). Authors' conclusions Hormone therapy for postmenopausal women with an intact uterus should comprise both estrogen and progestogen to reduce the risk of endometrial hyperplasia.

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  • Transplanted Adult Neural Progenitor Cells Survive, Differentiate and Reduce Motor Function Impairment in a Rodent Model of Huntington's Disease.

    Vazey, Elena; Chen, Kevin; Hughes, Stephanie; Connor, Bronwen (2006)

    Journal article
    The University of Auckland Library

    The present study investigated the ability for adult rat neural progenitor cells to survive transplantation, structurally repopulate the striatum and improve motor function in the quinolinic acid (QA) lesion rat model of Huntington's disease. Neural progenitor cells were isolated from the subventricular zone of adult Wistar rats, propagated in culture and labeled with BrdU (50 microM). Fourteen days following QA lesioning, one group of rats (n = 12) received a unilateral injection of adult neural progenitor cells ( approximately 180,000 cells total) in the lesioned striatum, while a second group of rats (n = 10) received a unilateral injection of vehicle only (sham transplant). At the time of transplantation adult neural progenitor cells were phenotypically immature, as demonstrated by SOX2 immunocytochemistry. Eight weeks following transplantation, approximately 12% of BrdU-labeled cells had survived and migrated extensively throughout the lesioned striatum. Double-label immunocytochemical analysis demonstrated that transplanted BrdU-labeled progenitor cells differentiated into either astrocytes, as visualized by GFAP immunocytochemistry, or mature neurons, demonstrated with NeuN. A proportion of BrdU-labeled cells also expressed DARPP-32 and GAD67, specific markers for striatal medium spiny projection neurons and interneurons. Rats transplanted with adult neural progenitor cells also demonstrated a significant reduction in motor function impairment as determined by apomorphine-induced rotational asymmetry and spontaneous exploratory forelimb use when compared to sham transplanted animals. These results demonstrate that adult neural progenitor cells survive transplantation, undergo neuronal differentiation with a proportion of newly generated cells expressing markers characteristic of striatal neurons and reduce functional impairment in the QA lesion model of Huntington's disease.

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  • Hierarchical titanium surface textures affect osteoblastic functions

    Zhao, C; Cao, Peng; Ji, W; Han, P; Zhang, J; Zhang, F; Jiang, Y; Zhang, X (2011)

    Journal article
    The University of Auckland Library

    This study investigated the surface characteristics and in vitro cytocompatibility of hierarchical textured titanium surfaces with nanograins and microroughness, produced by surface mechanical attrition treatment (SMAT). The surface characteristics were evaluated by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, contact angle, and surface energy measurements. The in vitro cytocompatibility of the SMAT processed surfaces (hereafter Ti-SMAT surfaces) were assessed in terms of cellular attachment, morphology, viability, alkaline phosphatase (ALP) activity, and mRNA gene expression. Two other titanium surfaces were compared: well-polished Ti6Al4V surfaces (hereafter Ti-polish surfaces) and thermally sprayed rough surfaces (hereafter Ti-spray surfaces). The Ti-SMAT surfaces showed a higher hydrophilicity and increased surface energy compared with the Ti-polish and Ti-spray surfaces. Consequently, these Ti-SMAT surfaces demonstrated enhancement of cell attachment, spreading, viability, and ALP activity. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed significantly higher ALP activity and stronger expression of mRNA levels of key osteoblast genes in cells grown on the Ti-SMAT surfaces than the other two surfaces. These results reveal a synergic role played by nanostructure and microtopography in osteoblastic functions and demonstrate the more promising cytocompatibility of the hierarchical textured surfaces. It is suggested that the SMAT process may provide a novel method of surface modification to the currently available metallic biomaterials.

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  • The GATE frame: critical appraisal with pictures (Editorial)

    Jackson, Rodney; Ameratunga, Shanthi; Broad, Joanna; Connor, Jennie; Lethaby, Elizabeth; Robb, Gillian; Wells, Linda; Glasziou, P; Heneghan, C (2006)

    Journal article
    The University of Auckland Library

    Epidemiologic evidence about the accuracy of diagnostic tests, the power of prognostic markers, and the efficacy and safety of interventions is the cornerstone of evidence-based health care ( 1). Practitioners of evidence-based health care require critical appraisal skills to judge the validity of this evidence. The members of the Evidence-Based Medicine (EBM) Working Group are international leaders in teaching critical appraisal skills, and their users' guides for appraising the validity of the health care literature ( 2) have long been the basis of teaching programs worldwide. However, we found that many of our students took a reductionist "paint by numbers" approach when using the Working Group's guides. Students could answer individual appraisal questions correctly but had difficulty assessing overall study quality. We believed that to be due to a poor understanding of epidemiologic study design. So, over the past 15 years of teaching critical appraisal we have modified the McMaster approach and developed the Graphic Appraisal Tool for Epidemiological studies (GATE) frame to help our students conceptualize the whole study as well as its components. GATE is a visual framework that illustrates the generic design of all epidemiologic studies (Figure 1). We now teach critical appraisal by "hanging" studies and the EBM Working Group's appraisal questions on the GATE frame. This editorial outlines the GATE approach to critical appraisal, illustrated throughout using the Heart and Estrogen/progestin Replacement Study (HERS), a randomized, double-blind, placebo-controlled trial of the effect of daily estrogen plus progestin on coronary heart disease (CHD) death in postmenopausal women ( 3). A detailed critical appraisal of HERS using a GATE-based checklist is available online ( 4).

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  • Magnetic and structural studies on copper(II) dialkyldithiocarbamates

    Boyd, Peter; MITRA, S; RASTON, CL; ROWBOTTOM, GL; WHITE, AH (1981)

    Journal article
    The University of Auckland Library

    The magnetic susceptibilities of a series of copper(II) dialkyldithiocarbamates have been measured over the range 4???290 K, the alkyl groups being methyl, ethyl, isopropyl, and n-butyl. Contrary to a previous report of strong ferromagnetic interaction in the diethyl derivative, we find no evidence of any significant exchange interaction in this compound. The dimethyl and di-isopropyl analogues show weak antiferromagnetic interactions. Only the di-n-butyl derivative in the dialkyl series shows evidence of strong magnetic exchange interaction but of an antiferromagnetic nature; this effect is peculiar to the phase recrystallized from chloroform???light petroleum (??), the phase obtained from chloroform???ethanol (??) showing no such interaction. To seek the origin of the exchange interaction in the ?? derivative, its crystal structure has been determined by single-crystal X-ray diffraction methods at 295 K and refined by least squares to a residual 0.032 for 1 976 ???observed??? reflections. Crystals are triclinic, P, a= 15.29(1), b= 9.963(7), c= 9.243(7)??, ??= 67.94(7), ??= 82.92(7), ??= 71.55(7)??, and Z= 2. The copper environment is the usual pseudo-square-planar array of four sulphur atoms from two bidentate ligands (???Cu???S???, 2.31 ??), but there is a long fifth interaction [Cu S, 2.899(4)??] through the inversion centre leading to pseudo-dimer formation. Although similar to the diethyl analogue in this respect, differences are observed in regard to (a) the bridging geometry in the ???dimer??? and (b) the proximity to the ???dimer??? sulphur ligands of sulphur atoms from neighbouring dimers at ca. 3.8 ??. The likely relative importance of these two features in determining the origin of the antiferromagnetic coupling is discussed. The structure of the ?? phase has also been determined, the final residual being 0.036 for 1 324 ???observed??? reflections. Crystals are monoclinic, P21/n, a= 14.593(5), b= 7.840(2), c= 10.822(5)??, ??= 101.55(3)??, and Z= 2. The molecules are located with the copper atoms on crystallographic centres of symmetry, and the only significant intermolecular interactions observed are S H contacts. The CuS4 entity is planar with ???Cu???S??? 2.30 ??.

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  • Association between maternal sleep practices and risk of late stillbirth: A case-control study

    Stacey, Tomasina; Thompson, John; Mitchell, Edwin; Ekeroma, Alec; Zuccollo, JM; McCowan, Lesley (2011)

    Journal article
    The University of Auckland Library

    Although a large number of studies have examined risk factors for stillbirth, few have explored a wide range of potential risk factors. Although little is known about the potential impact of sleep practices on the developing fetus, some studies have reported that sleeping supine may be associated with sleep-disordered breathing and lower maternal cardiac output in late pregnancy. The Auckland Stillbirth Study was a prospective population-based case-control study with the broad aim to identify modifiable risk factors for late stillbirth (???28 weeks' gestation). The present study explored the possibility that snoring, sleep position, and other sleep practices in pregnant women were associated with risk of late stillbirth. Participants were 155 singleton women with a late stillbirth (???28 weeks' gestation); matched controls were singleton women with ongoing pregnancies at the same gestational age as the stillbirths. Multivariable analysis adjusted for potential confounding factors. The primary study outcome measures were self-reported maternal snoring, daytime sleepiness (determined also with the Epworth sleepiness scale), and maternal sleep position both at the time of going to sleep and on waking (classified as left side, right side, back, and other). The prevalence of late stillbirth among the cohort was 3.09/1000 births. No association was found between risk of late stillbirth and either maternal snoring or daytime sleepiness. After adjustment for multiple potential confounding factors, the risk of late stillbirth was increased among women who slept on their back or their right side on the previous night compared with those who slept on their left side; the adjusted odds ratio (aOR) for back sleeping was 2.54, with a 95% confidence interval (CI) of 1.04-6.18, and for right side sleeping was 1.74, with a 95% CI of 0.98???3.01. The absolute risk of late stillbirth for women who went to sleep on their left side was half of those who did not go to sleep on their left (1.96/1000 vs. 3.93/1000). The risk of a late stillbirth was also lower in women who got up to go to the toilet once or less on the last night compared with those who got up more frequently (aOR, 2.28; 95% CI, 1.40???3.71). There was a higher likelihood for late stillbirth among women sleeping regularly during the day in the previous month in comparison with those who did not (aOR, 2.04; 95% CI, 1.26???3.27). These findings suggest that the risk of late stillbirth may be lower in pregnant women who sleep on their left side. This novel association requires confirmation before any recommendations can be made on optimal sleep position in late pregnancy.

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  • Competitive interaction degrades target selection: an ERP study.

    Hilimire, MR; Mounts, JR; Parks, NA; Corballis, Paul (2009-09)

    Journal article
    The University of Auckland Library

    Localized attentional interference (LAI) occurs when attending to a visual object degrades processing of nearby objects. Competitive interaction accounts of LAI explain the phenomenon as the result of competition among objects for representation in extrastriate cortex. Here, we examined the N2pc component of the event-related potential (ERP) as a likely neural correlate of LAI. In Experiment 1, participants responded to the orientation of a target while ignoring a nearby decoy. At small target-decoy separations, N2pc amplitude was attenuated whereas the amplitude of a later, positive component (Ptc) was potentiated. Experiment 2 ruled out sensory explanations of these effects. The N2pc results are consistent with the idea that spatially mediated competition for representation in extrastriate cortex degrades target selection. Moreover, the Ptc may reflect a bias signal needed to resolve the competition at smaller target-decoy separations.

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  • A complex intervention to support ???rest home??? care: a pilot study

    Sankaran, Shankar; Kenealy, Timothy; Adair, Allan; Adair, Vivienne; Coster, H; Whitehead, Noeline; Sheridan, Nicolette; Parsons, Matthew; Marshall, E; Bailey, L; Price, C; Crombie, D; Rea, Harold (2010)

    Journal article
    The University of Auckland Library

    Aims To describe an intervention supporting Aged Related Residential Care (ARRC) and to report an initial evaluation. Methods The intervention consisted of: medication review by a multidisciplinary team; education programmes for nurses; telephone advice ???hotlines??? for nursing and medical staff; Advance Care Planning; and implementing existing community programmes for chronic care management and preventing acute hospital admissions. Semi-structured interviews were conducted with members of the multidisciplinary team, rest home nurses and caregivers. Quantitative data were collected on medication changes, hotline use, use of education opportunities and admissions to hospital. Results Medications were reduced by 21%. Staff noted improvements in the physical and mental state of residents. There was no significant reduction in hospital admissions. Nurses were unable to attend the education offered to them, but it was taken up and valued by caregivers. There was minimal uptake of formal acute and chronic care programmes and Advance Care Planning during the intervention. Hotlines were welcomed and used regularly by the nurses, but not the GP. Conclusions The provision of high status specialist support on site was enthusiastically welcomed by ARRC staff. The interventions continue to evolve due to limited uptake or success of some components in the pilot.

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  • Cerebral asymmetries in monozygotic twins: An fMRI study

    Badzakova Trajkov, Gjurgjica; Haberling, Isabelle; Corballis, Michael (2010-08)

    Journal article
    The University of Auckland Library

    Lateralization for language, spatial judgment and face processing was assessed in 42 pairs of identical twins, 21 discordant and 21 concordant pairs for handedness, using fMRI. Individual laterality indices were calculated based on the observed activation patterns. All tasks showed expected asymmetry, favoring the left-hemisphere for language and the right-hemisphere for spatial judgment and face processing. The intra-class correlations on the laterality indices were significant only on the language task and only for the concordant group, but not the discordant group, suggesting a stronger genetic influence for language asymmetry in concordant twins. The expected asymmetry was greater for the concordant group only on the language task. The difference was not significant, but conformed quite well to Annett's genetic model, which assumes a right-shift (RS) gene with one allele (RS+) biasing toward right-handedness and left-cerebral language dominance, and the other (RS???) leaving both asymmetries to chance. The model also assumes that the genetic influence is additive for handedness but dominant-recessive for left-cerebral language dominance, which explains the high concordance for language dominance in twins discordant for handedness. Our data suggest that the same gene has no influence on right-hemisphere dominance for spatial judgment or face processing, and offer little support for mirror-imaging in MZ twins other than that due to chance.

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