13,307 results for Masters

  • Growth and movement of Blue Cod (Parapercis colias) in Paterson Inlet, Stewart Island, New Zealand

    Govier, Daniel (2001)

    Masters thesis
    University of Otago

    ix, 142 leaves :ill., map ; 30 cm. Bibliography: leaves 134-142. "December 2001." University of Otago department: Marine Science.

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  • The Epidemiology of Pertussis and Timeliness of Pertussis Immunisation in New Zealand

    Deane, Georgia Bailey (2015)

    Masters thesis
    University of Otago

    Introduction Despite increasing immunisation coverage in recent years, pertussis remains a leading cause of immunisation preventable disease in New Zealand. The current pertussis epidemic in New Zealand began in August 2011 and did not show signs of abating until May 2013. The current New Zealand immunisation schedule recommends that the first three doses of pertussis vaccine be received at six weeks, three months and five months of age. These are known as the primary series. A delay in receiving any dose of the primary series delays the time to developing effective immunity. It is not known how many children in New Zealand have delays between doses of pertussis vaccine, nor the extent of the delays. The aims of this study were as follows: 1. To provide an overview of the history of the epidemiology of pertussis as well as recent pertussis epidemiology in New Zealand. 2. To describe the coverage and timeliness of the primary series of pertussis immunisations for New Zealand and separately for children living in the greater Wellington region. 3. To detect differences in timeliness of immunisations by calendar year, socio-demographic characteristics, and by region for New Zealand and separately for children living in the greater Wellington region. An immunisation is considered not timely if it was not received within four weeks of the age specified by the New Zealand immunisation schedule. The definition of timeliness according to age works as long as the first vaccine dose is received at six weeks of age. However, if the first dose is received when the infant is older than six weeks, the timing of the second and third dose should be adjusted to maximise antibody production. Therefore, a second definition of timeliness was explored. Specifically, due dates for the second and third doses were calculated according to the recommended interval between doses. Between doses one and two the interval is scheduled to be six weeks. Between doses two and three the interval is scheduled to be two months. Methods The study population included all children born in New Zealand between 2007 and 2012 as recorded on the National Immunisation Register (NIR). Children excluded from the study were those: whose date of death was recorded as being before their date of birth, whose gender was recorded as ‘unknown’ or ‘indeterminate’, who were not included in the NIR (i.e opted off), who were not recorded as having received at least one pertussis vaccine dose, who had records of more than four pertussis vaccine doses, who had records of two pertussis vaccine doses within four weeks of each other, who were recorded as having died before receiving their first pertussis vaccine dose and who were recorded as receiving a pertussis vaccine dose before their date of birth. The study is a retrospective cohort study. The population was followed retrospectively over time to observe the occurrence of pertussis immunisation. Descriptive observations as well as multivariate regression analyses using ‘R’ were conducted. Results 371,587 children recorded in the National Immunisation Register were analysed for pertussis immunisation occurrence and timeliness. Timeliness of dose one was 89.0% for the whole New Zealand population. Timeliness of dose two was 87.8% and dose three was 83.1%. Overall 71.2% of the population received all three doses on time. Timeliness varied within each of the population subgroups of ethnicity, socio-economic deprivation, calendar year of vaccination and regions within New Zealand. Children of Asian ethnicity had the highest percentage of children receive all their immunisations on time (83.4%), followed by European ethnicity (76.3%). Māori had the lowest percentage with on time vaccination across all doses and had 52.5% of children receive all their immunisations on time. Timeliness was significantly different across all ethnicities (p<0.001). Discussion and conclusions This study found that only 71.2% of infants received all three pertussis doses on time leaving them vulnerable to infection themselves, and also acting as a source of infection for others. This immunisation deficiency may be contributing to pertussis remaining a poorly controlled disease in New Zealand with recurring epidemics resulting in large numbers of cases, hospitalisations and occasional deaths. On time immunisation varied across population groups and regions showing that there is work to be done to reduce these inequalities. There were significant differences between Māori and Pacific People and those living in areas of high socio-economic deprivation in particular. Policy concerning immunisation coverage and timeliness in New Zealand currently targets these populations and these results confirm that focus should remain on these groups if immunisation timeliness is to improve and rates of pertussis disease are to go down. This study shows that those who do not receive their first pertussis immunisation on time are more likely to have subsequent delays. This is an important finding which could guide interventions aimed at improving immunisation timeliness. Immunisation provides an ideal opportunity to connect with the parents or caregivers of the child, and educate them on the importance of immunisation timeliness to ensure that subsequent doses are received on time. Many primary care facilities in New Zealand have a system in place to contact parents and caregivers when their child is due for an immunisation, either by phone or mail. However, this contact can be easily forgotten when medical centres and other facilities become too busy or there are staff shortages. One solution may be to employ a dedicated nurse administrator, who is responsible for contacting parents to remind them that their child is due for an immunisation and to discuss with them the importance of timeliness. This is the first study in New Zealand to provide a comprehensive estimate of pertussis immunisation timeliness. Future research into whether the results from this study on immunisation timeliness correspond with rates of pertussis disease and hospitalisation would improve the understanding of the relationship between pertussis immunisation timeliness and disease occurrence.

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  • The Photochemistry of Organic Materials for Photonic Devices

    Middleton, Ayla Penelope (2014)

    Masters thesis
    Victoria University of Wellington

    Optically active organic chromophores have attracted much interest in recent years for their potential for use in photonic devices. Chromophores such as compound (1) have been found to have a very high second order nonlinear susceptibility ( β ) value of 650 × 10⁻³⁰esu in dimethyl formamide.¹ The performance of 1 in a polymer film is much lower than this due to the formation of aggregates which hinder the poling process necessary to ensure a noncentrosymmetric arrangement of the molecules in order to display second order nonlinear behaviour. The molecular aggregation behaviour of a set of second order nonlinear compounds based on compound 1 have been studied in this thesis. These compounds share the backbone shown in figure 1 with pendant groups added to the R₁ R₂ and R₃ positions, with the aim of finding substituent groups that can be added to the optically active merocyanine backbone that reduce the aggregation and increase the solubility of the compounds. This in turn will make them more suitable for use in photonics devices. It was found that a C₁₁H₂₃ alkyl chain added to the R₃ position made the largest contribution to decreasing aggregation. Bulky groups on the R₁ and R₂ positions also reduced aggregation. As a result compounds 5 and 8, with R₃ = C₁₁H₂₃ and bulky groups attached displayed the least aggregation of the compounds studied. ¹ See Figure 1 (pg. i): Merocyanine backbone with substituent positions marked.

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  • Stratigraphy, facies architecture and emplacement history of the c. 3.6 ka B.P. Ngatoro Formation on the eastern flanks of Egmont Volcano, western North Island, New Zealand

    Dixon, Benjamin John (2014)

    Masters thesis
    Victoria University of Wellington

    The Ngatoro Formation is an extensive volcaniclastic deposit distributed on the eastern lower flanks of Egmont Volcano, central North Island, New Zealand. Formally identified by Neall (1979) this deposit was initially attributed to an Egmont sourced water-supported mass flow event c. 3, 600 ¹⁴C years B.P. The Ngatoro Formation was subsequently described by Alloway (1989) as a single debris flow deposit closely associated with the deposition of the underlying Inglewood Tephra (c. 3,600 ¹⁴C yrs B.P) that had laterally transformed into a hyperconcentrated- to- flood flow deposit. Such water-supported mass flows have been well documented on volcanoes both within New Zealand (i.e. Mt Ruapehu) and elsewhere around the world (i.e. Mt Merapi, Central Java and Mt St Helens, Washington). This thesis comprises field mapping, stratigraphic descriptions, field and laboratory grain size and shape analysis, tephrochronology and palaeomagnetic analysis with the aim of refining the stratigraphy, facies architecture and emplacement history of the c. 3,600 ¹⁴C yrs B.P. Ngatoro Formation. This study has found that the Ngatoro Formation has a highly variable and complex emplacement history as evidenced by the rapid textural changes with increasing distance from the modern day Egmont summit. The Ngatoro Formation comprises two closely spaced mass flow events whose flow and emplacement characteristics have undergone both proximal to distal and axial to marginal transformations. On surfaces adjacent to the Manganui Valley on the deeply incised flanks of Egmont Volcano, the Ngatoro Formation is identified as overbank surge deposits whereas at the boundary of Egmont National Park it occurs as massive, pebble- to boulder-rich debris flow deposits. At intermediate to distal distances (17-23 km from the modern Egmont summit) the Ngatoro Formation occurs as a sequence of multiple coalescing dominantly sandy textured hyperconcentrated flow deposits. The lateral and longitudinal textural variability in the Ngatoro Formation reflects downstream transformation from gas-supported block-and-ash flows to water-supported debris flows, then subsequently to turbulent pebbly-sand dominated hyperconcentrated flows. Palaeomagnetic temperature estimates for the Ngatoro Formation at two sites (Vickers and Surrey Road Quarries, c. 10 km from the present day Egmont summit) indicate clast incorporation temperatures of c. 300°C and emplacement temperatures of c. 200°C. The elevated emplacement temperatures supported by the Ngatoro Formation’s coarse textured, monolithologic componentry suggest non-cohesive emplacement of block-and-ash flow debris generated by the sequential gravitational collapse of an effusive lava dome after the paroxysmal Inglewood eruptive event (c. 3,600 ¹⁴C yrs B.P.). The occurrence of a prominent intervening paleosol between these two events suggest that they are not part of the same eruptive phase but rather, the latter is a product of a previously unrecognised extended phase of the Inglewood eruptive event. This study recognises the potential for gravitational dome collapse, the generation of block-and-ash flows and their lateral transformation to water-support mass flows (debris, hyperconcentrated and stream flows) occurring in years to decades following from the main eruptive phase. This insight has implications with respect to the evaluation of post-eruptive hazards and risk.

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  • The Role of Identity in India’s Expanding Naval Power

    SinghSan, Sandeep (2015)

    Masters thesis
    University of Otago

    Since the end of the Cold War Indian political elites have demonstrated a remarkable predilection towards naval power in India’s grand strategy. Today, a naval modernization program is on the Indian agenda with emphasis on both the foreign acquisition and domestic construction of warships, submarines and battle fleets. The expensive capability accretion program is matched by a new penchant for articulating expansive naval doctrines and maritime strategy. This is a radical departure from the past where the Indian strategic community has often bemoaned the Indian political elite’s apparent ignorance of the potential of naval power. A number of reasons can be advanced to explain this change in the Indian political elite’s perception towards naval power. The predominant view in the literature favours material factors and India’s structural position as a source of this emerging maritime consciousness among the Indian political elite. While there are many compelling reasons for India to build a strong navy, this thesis suggests that an ideational factor related to India’s aspirations towards a new identity in the international system is an additional factor. India’s aspiration to become an Asia-Pacific power informs the Indian political elite’s new-found enthusiasm for naval power. As the Asia-Pacific region and the maritime disputes in the Asia-Pacific region assume growing importance in international politics, it is all the more important to understand India’s aspirations to transform itself into an Asia-Pacific power and how this shapes its naval strategy.

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  • Early Otago newspapers

    Clapperton, Barbara (1949)

    Masters thesis
    University of Otago

    INTRODUCTION. It has been said with much truth that the newspaper of today is one of the world’s most influential text books. It is thus easy to appreciate the still greater importance of the newspaper of seventy-five or more years ago. Our present world with its great advances in science, with the invention and development of the radio, the facsimile newspaper, television, radio-type and newsreels offers many challenges to the ordinary newspaper. Seventy-five years ago such opponents were not known, and the newspaper took first place as the only medium by which local news and overseas news were transmitted to the public. The relation of the daily paper to the community was very aptly summed up by Julius Vogel who wrote in the first leading article in the Otago Daily Times, 15 November, 1861, and reprinted in the Diamond Jubilee Issue, 1921 ---“The benefits arising from a daily newspaper are not to be exaggerated. Independent of the opportunity it affords to the community of making its wants felt and its wishes known to the outside world, and so asserting its dignity and advancing its importance, the moral, social, and commercial influences of a daily journal are strongly marked. It brings the members of a community into a closer unity; knits bonds of fellowship between them, not easily severed; facilitates business, advances the value of property, and in short mixes itself up so intimately with the daily events of life that, once having experienced its benefits, its absence is nothing short of a public calamity”. That the value of a newspaper in any community was recognised is borne out by the number established throughout Otago during its earliest years, not least important of which was the Otago News published in the same year as the arrival of “John Wickliffe” and the Philip Laing”. In outlying districts as population grew and as industry flourished, there came also the press, helped greatly by the impetus of goldseeking. It is with the development of these early newspapers, with their ambitions and struggles - and in many cases their failures - that I am here concerned, for they are the record of courage and endeavour inherent in the making up of those early colonists.

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  • Loss aversion in schizotypy: Investigating decision-making in those with a liability to schizophrenia

    Goss, Kate Laura (2015)

    Masters thesis
    University of Otago

    Loss aversion seems to be diminished or absent in schizophrenia patients, so the current study investigated this phenomenon in schizotypy. Undergraduate students from the University of Otago completed a hypothetical loss aversion task which involved naming prices at which they would be willing to buy or sell a one in ten chance to win a prize. One prize was mainly hedonic (a holiday) and the other was mainly utilitarian (paid rent). Loss aversion was measured by the ratio of prices participants were willing to accept when selling/willing to pay when buying. It was hypothesised that a majority of participants would show loss aversion, and this would be seen to a greater extent in the hedonic scenario than the utilitarian one. It was also hypothesised that components of schizotypy would be associated with reduced loss aversion, as would low anticipatory pleasure, poor memory and aberrant salience. Results showed that participants were biased towards avoiding loss. There was significantly more loss aversion for the hedonic than the utilitarian scenario as expected. There was no significant association between loss aversion and schizotypy although there was a slight trend in the expected direction shown by a near significant relationship between cognitive-perceptual schizotypy and low utilitarian loss aversion. There was also a significant relationship between low anticipatory pleasure and low utilitarian loss aversion, while there was no significant association between memory or aberrant salience and loss aversion. Overall, results suggest there may be a relationship between severity of illness and abnormal decision-making.

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  • Exploring educational efficiency in New Zealand primary and post-primary schooling, 1900-1945

    Frost, Anna Kathleen (1998)

    Masters thesis
    University of Otago

    vii, 83 leaves :col. ill., maps ; 30 cm. Includes bibliographical references. University of Otago department: Education. "March 31, 1998."

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  • Reproduction and population genetics of the New Zealand brooding brittle star Ophiomyxa brevirima

    Garrett, Frank Kim (1994)

    Masters thesis
    University of Otago

    x, 133 leaves :ill. (some col.) :30 cm. Includes bibliographical references. "December 1994." University of Otago department: Marine Science

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  • Antarctic gateway cities & contemporary mobility : a comparative analysis of the two Antarctic gateway cities of Christchurch & Hobart

    Grace, Michael Russell Ian (2005)

    Masters thesis
    University of Otago

    vii, 45 leaves :ill. ; 30 cm. Includes bibliographical references. University of Otago department: Tourism. "March 2005".

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  • Samurai Lear? : the cross-cultural intertexuality of Akira Kurosawa's Ran

    Gorringe, Karl (2007)

    Masters thesis
    University of Otago

    186 leaves ; 30 cm. Includes bibliographical references. University of Otago department: English. "Date: August 20, 2007."

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  • Aspects of uncertainty in private and public law

    Grant, Malcolm J. (1972)

    Masters thesis
    University of Otago

    xvi, 260, 6, 18, 10, 4, 21 leaves :ill. ; 30 cm. Includes bibliographical references. University of Otago department: Law.

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  • Copyright and its digital challenge : a comparison of New Zealand and German copyright law

    Gutman, Daniel (2006)

    Masters thesis
    University of Otago

    145, [17] leaves :ill. (some col.) ; 30 cm. Includes bibliographical references. University of Otago department: Law. "17 October 2006".

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  • John Grierson, the NZNFU and the art of propaganda

    Hoskins, David John (2007)

    Masters thesis
    University of Otago

    vii, 187 leaves ; 30 cm. Includes bibliographical references. "6 February 2007." University of Otago department: Media, Film and Communication.

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  • Re-colonisation of a relocated boulder reef in Tauranga Harbour, New Zealand

    Graeme, Lindsay Megan (1995)

    Masters thesis
    University of Otago

    109, xi leaves :music ; 27 cm. Bibliography: p. x-xi. University of Otago department: Marine Science. "March 1995."

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  • Genetic Analysis Of South Island Malignant Melanoma Cases

    Ahn, Jeong (2015)

    Masters thesis
    University of Otago

    Greater understanding of the pathological mechanisms underlying recurrent driver mutations is revolutionising the clinical management of melanoma. However given the association between UV radiation and UV-associated DNA mutagenesis, there are emerging indications that NZ may have a distinctive pattern of recurrent mutations more representative of high UV exposure. In order to gain insight into the frequency of recurrent mutations in NZ and how it may impact the clinical management of melanoma, this project encompassed three aims. The first aim was to determine a robust protocol for DNA extraction from FFPE melanoma tissue, and then optimise PCR amplification and sequencing of BRAF, NRAS and RAC genes, and the TERT promoter. The Qiagen FFPE extraction kit provided DNA of sufficient quality and quantity. Optimal PCR amplification required the combined use of shorter amplicon fragments, KAPA2G Robust polymerase enzyme, a touchdown PCR cycle and nested PCR. Lastly, the purification of sequenced DNA products required either the EDTA-ethanol wash or the unifilter plate-sephadex resin method. The second aim evaluated the analytical performance of the novel Immunohistochemistry (IHC)-based VEI monoclonal antibody test to detect the BRAF V600E mutation status in comparison to two reference methods, the Cobas assay, which is the only adopted test in NZ for BRAF mutation testing, and conventional Sanger sequencing. IHC demonstrated the highest sensitivity for the detection of BRAF V600E and V600E2 mutations, which supports its use as a supplementary screening assay for determining the BRAF-mutant genotype. The final aim was to determine the frequency of recurrent mutations in the BRAF, NRAS and RAC1 genes and the promoter of TERT in South Island melanoma patients using 95 melanoma tissues from 87 patients with Sanger sequencing. A distinctive pattern of recurrent mutations was observed, which may be representative of chronic UV exposure. This included a relatively high frequency of melanomas wild-type for BRAF and NRAS mutations and a higher frequency of primary melanomas with TERT promoter mutations compared to studies in USA or Europe. This would then suggest that therapeutic regimes that target the non-BRAF-NRAS mutant subgroup and those with TERT promoter mutations may become more relevant in NZ. The results from the BRAF mutation study were compared with 2 external studies, a study using North Island melanoma samples (Wellington) and a study carried out on a national scale (Auckland, Tauranga and Christchurch). The frequency of the BRAF V600E mutation was found to be relatively low in NZ compared to USA or Europe. This is consistent with BRAF V600E mutations having an inverse association with chronic UV damage. Moreover, the low BRAF V600E mutation rate indicates the clinically approved targeted inhibitors for BRAF-mutant melanomas may be less relevant in the NZ population. The BRAF V600K mutation rate was found to be higher in the North Island compared to the South Island, which highlights a potential difference in mutation frequency between geographical locations within NZ. Overall, this study provides new insights of regarding a distinctive pattern of recurrent mutations in the South Island of NZ and NZ, more representative of chronic UV exposure. Furthermore this indicates the clinical management of melanoma may also be slightly different in NZ.

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  • A useful accessory: The use of lightweight replica ornament to manage the cultural heritage values of earthquake-prone buildings

    Smith, Moira (2015)

    Masters thesis
    Victoria University of Wellington

    In NZ, some earthquake-prone heritage buildings have, historically, been restored with lightweight replica ornament to reconstruct decorative features that have been damaged or removed over time. But restoration has traditionally been a contested approach to conservation, particularly when heritage values and authenticity are considered to be intrinsic only to original or historic built fabric. This problem leads to the central research question addressed in this dissertation: ‘Can lightweight replica ornament be used to manage the heritage value of earthquake-prone heritage buildings?’ The research draws on Critical Heritage Studies which challenges the conventional stress on the intrinsic value of tangible heritage objects, and argues that heritage value is found in the intangible cultural processes that surround things. Consequently, authenticity is seen as pluralised and dependent on the cultural concerns, and aspirations, of local stakeholder communities. Using the theoretical framework of critical heritage and material culture studies, this dissertation therefore examines a technical aspect of conservation practice by re-theorising the concept of 'restoration'. The research methodology employs an adapted model of Action Research to investigate current professional practice. After analysing the historical context of earthquake-prone heritage buildings in the first chapter, in chapter two qualitative interviews are conducted with professionals who have an interest in the management of earthquake-prone buildings. Through the analysis and discussion of this data, a new actor network model is developed which shows the wider context of the resolution of the earthquake-prone status of heritage buildings. The findings suggest that professionals believe that heritage value is intrinsic to built fabric, and that the repair of existing built fabric is generally achievable. This means that replica ornament should only be considered for situations where reparability is unfeasible, and that lightweight substitute materials should only be used where traditional materials and technologies can longer be reproduced. Within these constraints it is possible to use lightweight replica ornament where it can be justified as a contributor to cultural heritage values. Furthermore, where professionals can reconcile the varying concerns of stakeholder communities in terms of safety and heritage value then lightweight replica ornament has the potential to add meaning to buildings and to become part of the narrative of place.

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  • High Impedance Amplifiers for Non-Contact Bio-Potential Sensing

    Ryan, Brett (2013)

    Masters thesis
    Victoria University of Wellington

    This research develops a non-contact bio-potential sensor which can quickly respond to input transient events, is insensitive to mechanical disturbances, and operates with a bandwidth from 0.04Hz – 20kHz, with input voltage noise spectral density of 200nV / √Hz at 1kHz. Initial investigations focused on the development of an active biasing scheme to control the sensors input impedance in response to input transient events. This scheme was found to significantly reduce the settling time of the sensor; however the input impedance was degraded, and the device was sensitive to distance fluctuations. Further research was undertaken, and a circuit developed to preserve fast settling times, whilst decreasing the sensitivity to distance fluctuations. A novel amplifier biasing network was developed using a pair of junction field effect transistors (JFETs), which actively compensates for DC and low frequency interference, whilst maintaining high impedance at signal frequencies. This biasing network significantly reduces the settling time, allowing bio-potentials to be measured quickly after sensor application, and speeding up recovery when the sensor is in saturation. Further work focused on reducing the sensitivity to mechanical disturbances even further. A positive feedback path with low phase error was introduced to reduce the effective input capacitance of the sensor. Tuning of the positive feedback loop gain was achieved with coarse and fine control potentiometers, allowing very precise gains to be achieved. The sensor was found to be insensitive to distance fluctuations of up to 0.5mm at 1Hz, and up to 2mm at 5kHz. As a complement to the non-contact sensor, an amplifier to measure differential bio-potentials was developed. This differential amplifier achieved a CMRR of greater than 100dB up to 10kHz. Precise fixed gains of 20±0:02dB, 40±0:01dB, 60±0:03dB, and 80±0:3dB were achieved, with input voltage noise density of 15nV / √Hz at 1kHz.

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  • Biology of the sea pen Pteroeides sp. in Fiordland, New Zealand

    Duncan, Joanne Claire (1998)

    Masters thesis
    University of Otago

    281 leaves ; 30 cm. Includes bibliography. "August 1998". University of Otago department: Marine Science.

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  • The impact of hyperuricemia on pancreatic beta-cell function and the development of diabetes mellitus

    Johnstone, Ryan Davic (2015)

    Masters thesis
    University of Otago

    Uric acid or urate is an organic anion produced in the liver from alcohol, fructose and protein metabolism. Urate levels in humans are much higher than that of other animals, sometimes by a factor of 10. The most commonly thought of disease associated with high urate levels, or hyperuricemia, is gout. Historically gout was colloquially known as the ‘kings disease’, whereby only the kings could consume large quantities of meat and alcohol thereby raising urates levels. Nowadays, many people are able to ‘eat like kings’, in that high calorific foods are readily available and cheap. As a consequence urate levels around the world have increased and are still rising. In parallel with this treat is the much well publicised disease of diabetes mellitus. Type 2 Diabetes mellitus (T2DM) is considered, by many, as the biggest health issue of the 21st century. With that in mind, this project sets out to provide evidence that urate may be a contributing factor in T2DM. The two characteristics of T2DM that this project will focus around are a reduction in insulin secretion and reduced β-cell mass. AMP-activated protein kinase (AMPK) is considered the major cellular energy sensor. The protein is responsive to changes in ATP:ADP ratio within the cell and able to coordinate a wide range of downstream pathways once activated/phosphorylated. It is a key target in the treatment of diabetes whereby its activation in liver, adipose and skeletal muscle lower blood glucose levels and increase insulin sensitivity. However, it has counterproductive effects in pancreatic β-cells whereby its activation inhibits insulin secretion and may even promote apoptosis. The other target in this project is the microRNA miR-34a. MiR-34a has negative effects on cell survival such as inhibiting cell cycle progression and promoting apoptosis. What’s interesting about this microRNA, and particularly relevant for this project, is that miR-34a has been shown to be the one of the most consistent microRNAs the expression of which increases under diabetic conditions. Its elevated expression in circulating plasma of pre-diabetes has even been suggested as a marker for type-2 diabetes development. In this study I tested whether hyperuricemic conditions influence the expression of AMPK and miR-34a in cultured pancreatic β-cells and I postulate that the urate transporter GLUT9 is the transporter responsible for the urate-induced effects. Hyperuricemic conditions increased the expression of the α1-AMPK subunit and miR-34a after chronic exposures. Hyperuricemia also activated apoptotic cascades and reduced cell viability, which was attenuated with urate transport inhibition. Lastly, siRNA knockdown of GLUT9 significantly reduced the increase in miR-34a expression under hyperuricemic conditions providing evidence for GLUT9 as the primary urate transporter in β-cells. Because the above experiments were carried out in both mouse and human cells this may reflect that urate regulates basic (conserved) mechanisms in β-cells. In light of this, pathological hyperuricmia may contribute to reduced insulin secretin and β-cell death and therefore be implicated in the development of T2DM.

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