231 results for Conference poster

  • Synthesis and mechanistic studies of PLA₂ inihibition by the marine alkaloid hyrtiosulawesine

    Liew, Lydia; Bourguet-Kondracki, M-L; Copp, Brent (2010-10-17)

    Conference poster
    The University of Auckland Library

    The first isolation of hyrtiosulawesine (1) was from an Indonesian collection of the marine sponges Hyrtios erectus and H. reticulatus.1 The β-carboline alkaloid was subsequently re-isolated from a Red Sea collection of Hyrtios sp. and found to display anti-phospholipase A2 (PLA2) activity with an IC50 value of 14 μM. Phospholipase A2 catalyses the hydrolysis of membrane phospholipids at the sn-2 position to generate arachidonic acids (AA).3,4 AA are precursors to a large family of compounds known as the eicosanoids associated with inflammatory reactions.4 PLA2 inhibition by hyrtiosulawesine would lead to a decrease in AA and proinflammatory eicosanoids, with anti-inflammatory effect.4 In an effort to understand the structural attributes of the natural product (1) that cause PLA2 inhibition, hyrtiosulawesine and a series of related model compounds (2, 3) will be synthesised and evaluated for biological activity. Biomimetic nucleophiles will be used to probe hyrtiosulawesine and related compounds in order to determine their reactivity and possible site of reaction. Bioactive members of the library of compounds will subsequently be subjected to reaction with bee venom phospholipase A2 to identify the presence of any covalent adducts. Further studies may be directed to discovering the nature and location of the covalent linkage within the enzyme active site. The latest results will be presented. References 1. Salmoun, M.; Devijver, C.; Daloze, D.; Braekman, J.-C.; Van Soest, R. W. M. J. Nat. Prod. 2002, 65, 1173-1176. 2. Sauleau, P.; Martin, M.-T.; Dau, M.-E. T. H.; Youssef, D. T. A.; Bourguet-Kondracki, M.-L. J. Nat. Prod. 2006, 69, 1676-1679. 3. Balsinde, J.; Balboa, M. A.; Insel, P. A.; Dennis, E. A. Annu. Rev. Pharmacol. Toxicol. 1999, 39, 175-189. 4. Parente, L. J. Rheumatol. 2001, 28, 2375-2382.

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  • Polyamine diamide orthidine F as a potent and selective antimalarial lead compound

    Liew, Lydia; Kaiser, M; Copp, B (2013)

    Conference poster
    The University of Auckland Library

    THE POLYAMINE DIAMIDE ORTHIDINE F AS A POTENT AND SELECTIVE ANTIMALARIAL LEAD COMPOUND Orthidine F (1) was isolated from an extract of the marine organism Aplidium orthium, found at Three Kings Islands, New Zealand.1 An initial screen of the natural product 1 against a panel of parasitic protozoa (Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Plasmodium falciparum K1 dual drug-resistant strain) identified selective inhibitory activity for T. brucei rhodesiense (IC50 78 μM) against T. cruzi, no detectable activity towards L. donovani and moderate activity against P. falciparum. Furthermore, the natural product was found to be non-toxic in the non-malignant L6 rat myoblast cell line, thus representing an attractive target as an antiparasitic drug. A preliminary structure-activity relationship (SAR) study identified analogues with a similar activity profile to the natural product. The analogues were found to exhibit moderate inhibitory activity against T. brucei rhodesiense (IC50 3.2–210 μM), more potent inhibitory activity against P. falciparum (IC50 0.0086–0.61 μM), and no significant activity against T. cruzi and L. donovani. The analogues also continued to display little or no cytotoxic effect in the L6 cell line, this combined with the potent IC50 values obtained for inhibition of P. falciparum afforded a series of analogues with impressive properties which warranted further studies. This led to a second series of analogues with the intention of improving its antimalarial activity. The analogues generated from this exercise exhibited potent in vitro activities (IC50 0.0086–0.61 μM) while retaining selectivity against P. falciparum. Three analogues were selected based on the in vitro data obtained and evaluated for in vivo activity in the Plasmodium berghei mouse model of malaria; which in this instance did not yield significant activity.

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  • Estado nutricional de los indígenas Pataxó de 5 aldeas de Minas Gerais, Brasil

    Castro, TG; Oliveira, SNLG; Mazzetti, CMS; Conde, WL; Leite, MS; Pimenta, AM (2012-11-13)

    Conference poster
    The University of Auckland Library

    Introducción: En las últimas décadas los estudios brasileños sobre el estado nutricional no incluyeron la población indígena como un segmento de análisis, generando brechas de informaciones para el direccionamiento de políticas de alimentación y nutrición para el grupo. Objetivo: Evaluar el estado nutricional de los indígenas Pataxó de 5 aldeas de Minas Gerais. Metodología: Estudio transversal que evaluó 257 indígenas (87,4% del total) en 2011. El peso y la altura fueran evaluados conforme las orientaciones de la OMS. La circunferencia de la cintura (CC) fue tomada en el punto medio entre la cresta ilíaca y la última costilla. Las clasificaciones nutricionales fueron hechas a partir de los índices altura para edad (A/E), índice de masa corporal para edad (IMC/E), índice de masa corporal (IMC) y CC, utilizando las referencias de la OMS y de Lipschitz (para ancianos). Resultados: Fueron evaluados 70 niños (27,3%), 59 adolescentes (23,0%), 116 adultos (45,0%) y 12 ancianos (4,7 %). Ninguno de los niños presentó déficit para A/E, 1,4% presentaron bajo IMC/E y 2,9% peso elevado para IMC/E. Fue observado déficit de altura en 3,4% de los adolescentes y peso excesivo (IMC/E) en 8,5%. Altas prevalencias de sobrepeso/obesidad y valores elevados de CC fueron apuntados para adultos (56,0% y 56,8 %, respectivamente) y ancianos (25,0% y 75%, respectivamente). Conclusión: Se destacan el exceso de peso en la población de forma ascendente desde la niñez y la baja frecuencia de déficits nutricionales entre niños y adolescentes. Financiación: Fundação de Amparo à Pesquisa do Estado de Minas Gerais.

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  • Kai Time in ECE Survey

    Gerritsen, Sarah; Morton, Susan; Wall, C (2014-06-11)

    Conference poster
    The University of Auckland Library

    Kai Time in ECE is a one-off online survey collecting information about nutrition and physical activity practices and policies for 3-4 year olds in licensed Early Childhood Education (ECE) services in Auckland, Counties Manukau and Waikato. The survey results will be used in PhD research on the influence of childcare on preschool dietary patterns and body size.

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  • The potential of urban forests to mitigate atmospheric CO2 concentrations

    Weissert, Lena; Salmond, Jennifer; Schwendenmann, Luitgard (2013)

    Conference poster
    The University of Auckland Library

    The urban population in New Zealand is expected to increase significantly over the next years. Urban areas are generally large sources of anthropogenic carbon dioxide (CO2) emissions. However, attempts to quantify atmospheric CO2 concentrations and fluxes have suggested that densily vegetated urban areas may absorb sufficient quantities of anthropogenic CO2 to act as a local sink. Consequently, urban greening programs now form an important part of many urban climate change mitigation policies globally as well as in New Zealand. However, knowledge about the direct contribution of urban vegetation on atmospheric CO2 concentrations is still limited and measurements scarce. This paper examines the methods used to date to estimate / measure carbon pools and CO2 fluxes from urban vegetation and soils (collectively known as urban forests) and aggregates currently available results. Results from the northern hemisphere show that carbon pools in urban forests were comparable to 3 – 60% of the annually released fossil fuel emissions, while photosynthetic uptake accounted for 0.3 – 2.6% of the total estimated emissions in urban areas. Whilst vegetation did not offset CO2 emissions on an annual basis in these scenarios, vegetative CO2 uptake resulted in significantly lower atmospheric CO2 concentrations in summer. However, the currently available results are related to a large degree of uncertainty due to the limitations of the applied methods, the limited number of urban areas studied and the temporal / spatial resolution of the fieldwork. This paper demonstrates that in order to effectively quantify and encorporate carbon fluxes from urban areas into annual CO2 budgets, future research needs to use a combination of methodologies and be aware of the scales of their studies. Thus, before investing in urban greening programs the potential of urban vegetation as a climate change mitigation measure needs to be further investigated, particularly for cities in the southern hemisphere.

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  • Reverse Mentoring: Benefits and Barriers

    Ross, M; Dunham, Annette (2015)

    Conference poster
    The University of Auckland Library

    Background: Current research suggests that the modern workforce is comprised of a substantial proportion of ageing employees, in addition to an influx of young, first-time workers. This diverse and multigenerational workforce provides organisations an interesting challenge, in retaining engaged and productive employees, and ensuring relevant training and development. One specific management practice is reverse mentoring. Reverse mentoring is a unique form of mentoring, whereby the traditional roles of mentor and mentee are reversed. It involves a junior employee (in age/status) mentoring a senior employee. The junior employee is able to share their recent generational learnings and perspective with a senior organisational member, who gains insight into recent trends and technologies. Whilst there appear to be many benefits from this relationship, including increased communication and understanding; leadership development; and upskilling in relevant trends, there may also be some barriers to the success of the relationship. Barriers may include a resistance to the shift in power hierarchy and challenges with changing the traditional learning pedagogy of older teacher and younger learner. Aim: Reverse mentoring is a reasonably modern concept, and as such, empirical research on this practice is relatively new. This research aims to explore any benefits and barriers experienced in a reverse mentoring relationship. Method: Participants in this study will be recruited from a Melbourne hospital, who currently run a formal reverse mentoring relationship program. Approximately 16 individuals (8 mentors and 8 mentees), will be invited to participate. The proposed study uses a qualitative method of data collection, through semi-structured interviews. Interviews will be recorded, and responses will be transcribed, with thematic analysis used to identify common themes. Thematic analysis allows the common themes and experiences of mentors and mentees, to tell an overall story of the data. Conclusion: The proposed study’s findings contribute to a currently small base of research on reverse mentoring. It is hoped that the research will help (i) inform future quantitative research on reverse mentoring and (ii) inform organisational strategies that will help employees engage in reverse mentoring relationships in ways that effectively support their training and development.

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  • CO2 Fluxes and Concentrations in a Residential Area in the Southern Hemisphere

    Weissert, Lena; Salmond, Jennifer; Turnbull, JC; Schwendenmann, Luitgard (2014-12-15)

    Conference poster
    The University of Auckland Library

    While cities are generally major sources of anthropogenic carbon dioxide (CO2) emissions, recent research has shown that parts of urban areas may also act as CO2 sinks due to CO2 uptake by vegetation. However, currently available results are related to a large degree of uncertainty due to the limitations of the applied methods and the limited number of studies available from urban areas, particularly from the southern hemisphere. In this study, we explore the potential of eddy covariance and tracer measurements (13C and 14C isotopes of CO2) to quantify and partition CO2 fluxes and concentrations in a residential urban area in Auckland, New Zealand. Based on preliminary results from autumn and winter (March to July 2014) the residential area is a small source of CO2 (0.11 mol CO2 m-2 day-1). CO2 fluxes and concentrations follow a distinct diurnal cycle with a morning peak between 7:00 and 9:00 (max: 0.25 mol CO2 m-2 day-1/412 ppm) and midday low with negative CO2 fluxes (min: -0.17 mol CO2 m-2 day-1/392 ppm) between 10:00 and 15:00 local time, likely due to photosynthetic CO2 uptake by local vegetation. Soil CO2 efflux may explain that CO2 concentrations increase and remain high (401 ppm) throughout the night. Mean diurnal winter delta13C values are in anti-phase with CO2 concentrations and vary between -9.0 - -9.70/00. The depletion of delta13C compared to clean atmospheric air (-8.20/00) is likely a result of local CO2 sources dominated by gasoline combustion (appr. 60%) during daytime. A sector analysis (based on prevailing wind) of CO2 fluxes and concentrations indicates lower CO2 fluxes and concentrations from the vegetation-dominated sector, further demonstrating the influence of vegetation on local CO2 concentrations. These results provide an insight into the temporal and spatial variability CO2 fluxes/concentrations and potential CO2 sinks and sources from a city in the southern hemisphere and add valuable information to the global database of urban CO2 fluxes.

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  • Development of an organisational memory scale

    Dunham, Annette (2007-12-06)

    Conference poster
    The University of Auckland Library

    In many countries, people are retiring earlier than ever before and the retirement of the baby boom generation over the next two decades further intensifies the impact of this trend. Accompanying this development, are fears about the potential loss of organisational knowledge or memory which may equate to the loss of the organisation’s competitive advantage. Organisations, while recognizing that older workers often possess valuable “organisational memory” seem to also assume these same workers will readily divest themselves of their knowledge. Encouraging experienced workers to act as a mentor to younger or less experienced workers, is often mentioned in the management and related literature as a way of capturing and retaining valuable organisational knowledge. However, employees (including older workers) in the possession of considerable organisational memory, may, or may not be willing to divulge their knowledge to others, for a number of reasons. This poster presents initial results from the first of a series of studies designed to examine the relationship between organisational memory in the individual and propensity to mentor. It outlines the development and exploratory factor analysis of an “Organisational Memory” scale that taps the individual’s own resources in terms of organisational knowledge and expertise. Subsequent studies in the proposed research aim to help organisations more effectively target potential mentors for the purposes of retaining organisational knowledge, while also identifying the relevant costs and benefits of mentoring perceived by those individuals. By doing so it is hoped organisations will have a clearer understanding of how they can minimize costs while emphasising the benefits of such a relationship for the potential mentor. In contrast to the “development outcomes” focus of much of the mentoring literature, these studies give attention to the “knowledge sharing role of mentoring, while also touching on developmental outcomes, in this case, for the mentor

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  • Measuring the electrical impedance of mouse brain cortex

    Wilson, MT; Elbohouty, M; Lin, Oliver; Voss, LJ; Jones, K; Steyn-Ross, DA (2014)

    Conference poster
    The University of Auckland Library

    We report on an experimental method to measure conductivity of cortical tissue. We use a pair of 5mm diameter Ag/AgCl electrodes in a Perspex sandwich device that can be brought to a distance of 400 microns apart. The apparatus is brought to uniform temperature before use. Electrical impedance of a sample is measured across the frequency range 20 Hz-2.0 MHz with an Agilent 4980A four-point impedance monitor in a shielded room. The equipment has been used to measure the conductivity of mature mouse brain cortex in vitro. Slices 400 microns in thickness are prepared on a vibratome. Slices are bathed in artificial cerebrospinal fluid (ACSF) to keep them alive. Slices are removed from the ACSF and sections of cortical tissue approximately 2 mm times 2 mm are cut with a razor blade. The sections are photographed through a calibrated microscope to allow identification of their cross-sectional areas. Excess ACSF is removed from the sample and the sections places between the electrodes. The impedance is measured across the frequency range and electrical conductivity calculated. Results show two regions of dispersion. A low frequency region is evident below approximately 10 kHz, and a high frequency dispersion above this. Results at the higher frequencies show a good fit to the Cole-Cole model of impedance of biological tissue; this model consists of resistive and non-linear capacitive elements. Physically, these elements are likely to arise due to membrane polarization and migration of ions both intra- and extra-cellularly.

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  • Recent experiences in using TOUGH2 for geothermal modelling

    Clearwater, Emily; Yeh, Angus; O'Sullivan, John; Kaya, Eylem; Croucher, Adrian; Cui, T; OSullivan, Michael; Zarrouk, Sadiq; Austria, JJC; Ciriaco, Anthony; Archer, Rosalind; Dempsey, David (2012-04-17)

    Conference poster
    The University of Auckland Library

    The geothermal modelling group in Engineering Science (University of Auckland) is involved with several geothermal R&D projects. On the development side we are running models of Ohaaki, Wairakei, Ngawha, Reporoa, Wayang Windu and Lihir. Our experiences in these projects have led on to several parallel research projects. Our model of Wairakei-Tauhara is so large that it also contains the Rotokawa system and the edge of the Ngatamriki system. Trying to understand the large-scale convection process at Wairakei-Tauhara has led on to studies of more generic convection studies and studies of larger areas of the TVZ. It has also led on to deeper models which require equations of state that can handle high pressures and temperatures. We have developed one for pure water but now wish to extend it to include CO2 and NaCl. With larger and larger models the computational demand increases quickly and we are now routinely using TOUGH_MP, the parallel version of TOUGH2. Also with large complex models dealing with input and output is a major task and we have developed a suite of PYTHON scripts (called pyTOUGH) for carrying out several model management tasks. One of the biggest challenges in geothermal modelling is model calibration and we have carried out studies using inverse modelling with iTOUGH and PEST and also Markov Chain Monte Carlo methods (MCMC). We are also carrying out miscellaneous studies of resewrvoir physics several of which involve fluid/rock interaction, for example the effects of cold water injection on permeability and subsidence in geothermal fields.

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  • Is keratoconus a case of matrix remodelling gone crazy?

    Brookes, Nigel; Loh, IP; Clover, GM; Poole, CA; Sherwin, Trevor (2002)

    Conference poster
    The University of Auckland Library

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  • Visual Acuity, Refractive Status and Accommodation in Octopus Gibbsi

    Tunrbull, P; Backhouse, Simon; Phillips, John (2010-07-27)

    Conference poster
    The University of Auckland Library

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  • What should be stored in Biobanks? Using computational modelling to unravel genotype to phenotype linkage

    Cooling, Michael; Atalag, Koray (2016-10-31)

    Conference poster
    The University of Auckland Library

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  • Investigation into the racemic X-ray structure of the antimicrobial protein snakin-1

    Yeung, Ho; Yosaatmadja, Yuliana; Squire, Christopher; Harris, Paul; Baker, Edward; Brimble, Margaret (2015-10-22)

    Conference poster
    The University of Auckland Library

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  • Gelation of oxidised cereal beta-glucan extracts

    Mohan, Anand (2014-02-21)

    Conference poster
    The University of Auckland Library

    Cereal β-glucan, which occurs in plant cell walls, is the major component of soluble dietary fiber in oat and barley. Soluble fibers with a high solution viscosity, which is positively correlated to molecular weight (MW), lower the serum glucose and cholesterol levels. The relevant health claims on β-glucan as a functional food have been allowed by regulatory authorities, including the EFSA and the US FDA. In most processed-food systems, the native hydrolytic enzymes are inactivated, but oxidative degradation of this non-starch polysaccharide can, however, adversely affect the claimed health benefits. (Kivelä 2011). Although the physiological benefits are positively correlated with the viscosity of β-glucan, the relationship with its gelling capacity is not fully understood. The scope of the Master’s thesis included (1) the study of gelation characteristics of oxidised solutions of oat and barley β-glucan, and (2) correlating the results obtained by dynamic light scattering (DLS) microrheology with conventional rheology.

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  • Radiofrequency ablation of osteoid osteoma - aiming for zero recurrence

    Doyle, Anthony; Graydon, A; French, JG; Hanlon, M (2016-04-30)

    Conference poster
    The University of Auckland Library

    Over a 13 year period, a single radiologist (AJD) performed radiofrequency ablation (RFA)of osteoid osteoma in 32 patients. The lesions were located mostly in the lower extremities (femur N=15, tibia N=9) and spine (N=5). Lesion size varied from 4 to 18 mm, average 10 mm. Patient age ranged from 5 to 23 years, average 14 years. All but two had RFA as their primary treatment, with two treated after surgical excision had resulted in recurrence. CT guidance was used for all procedures, performed under general anaesthetic. A variety of different radiofrequency generators and probes were used. No complications occurred. None of the patients showed any signs of recurrence and none required further intervention. Although the followup period varied (and a few patients were lost to followup after a few weeks), most of the patients were followed for at least 12 months post procedure, with maximum followup seven years. We conclude that, with careful technique, the recurrence rate for RFA of osteoid osteoma can approach zero. Details of technique are discussed in the poster itself.

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  • Neonatal invasive pneumococcal disease in NewZealand in the era of conjugate pneumococcal vaccination 2009 - 2013

    Burton, C; Mount, V; Jackson, C; Heffernan, H; Best, Emma (2014-11-19)

    Conference poster
    The University of Auckland Library

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  • Appropriate Antibiotics for Empyema at Starship Children’s Hospital

    Burton, C; Price, Neil; Best, Emma (2014-11-19)

    Conference poster
    The University of Auckland Library

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  • Reducing the Risks of Long-Term Human Space Exploration by Simulating Missions in an Analog Environment on Mauna Loa

    Binsted, K; Hunter, JB; Caldwell, Bryan (2012-02)

    Conference poster
    The University of Auckland Library

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  • The STn-SNc hyperdirect pathway modulates dopaminergic neuron activity by inhibiting GABAergic inputs from the SNr via endocannabinoids

    Freestone, Peter; Wu, XH; de Guzman, G; Lipski, Janusz (2014-07-05)

    Conference poster
    The University of Auckland Library

    The hyperdirect pathway of the basal ganglia circuitry terminates with a glutamatergic projection from the Subthalamic Nucleus (STN) to the Substantia Nigra pars compacta (SNc). We recently showed that glutamate released in the SNc drives endocannabinoid production in dopaminergic neurons, which in turn inhibits GABAergic transmission in that region. The present study investigated the potential role of STN glutamatergic projections of the hyperdirect pathway in this novel endocannabinoid modulatory mechanism. Whole-cell patch-clamp recordings were made from SNc dopaminergic neurons in horizontal brain slices (rat) containing STN, SNc and Substantia Nigra pars reticulata (SNr) regions. Either electrical (bi-polar electrode) or pharmacological (local carbachol application) stimulation of the STN was performed to evoke selective glutamate release from terminals in the SNc. GABAergic inputs to the SNc from the SNr were electrically stimulated to evoke inhibitory post-synaptic currents (eIPSCs). Single-pulse electrical stimulation of the STN caused transient (< 1 sec) attenuation of GABAergic eIPSCs amplitudes recorded from dopaminergic neurons (to 73% of control). The eIPSC attenuation was prevented by block of either cannabinoid CB1 receptors with rimonabant (3 µM) or metabotropic glutamate mGluR1 receptors with CPCCOEt (100 µM). Pharmacological activation of STN neurons by rapid local perfusion of muscarinic agonist carbachol (100 µM, 10 s) caused a similar attenuation of eIPSC amplitude. These findings show that glutamate release from STN terminals in the SNc modulates GABAergic transmission through endocannabinoid signalling – a previously undescribed function of the hyperdirect pathway.

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