32 resultados para 16-163

em Queensland University of Technology - ePrints Archive


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Recombinant human papillomavirus (HPV) virus-like particles (VLPs) made from the major capsid protein L1 are promising vaccine candidates for use as vaccines against genital and other HPV infections, and particularly against HPV-16. However, HPV-16 genotype variants have different binding affinities for neutralising mouse Mabs raised against HPV-16 L1 VLPs. This paper analyses, using a panel of well-characterised Mabs, the effects on the antigenicity of various C- and N-terminal deletants of HPV-16 L1 made in insect cells via recombinant baculovirus, of an A → T mutation at residue 266 (A266T), and of a C → G mutation at conserved position 428 (C428G). The effects of these changes on assembly of the variant L1s were studied by electron microscopy. Binding of Mab H16:E70 to A266T was reduced by almost half in comparison to wild type L1. Retention of the C-terminal region 428-483 was critical for the binding of conformation-specific Mabs (H16:V5, H16:E70, H16:U4 and H16:9A) whereas deletion of the nuclear localisation signal (NLS) or the C428G mutation or an N-terminal deletion (residues 2-9) did not affect the antigenicity. The N-terminal deletion resulted in a mixed population of 30 and 55 nm VLPs, which differs from the same construct expressed in Escherichia coli, whereas pentamer aggregates resulted from deletion of the 428-465 region or the C428G mutation. The results have implications both for considering use of single-genotype HPV vaccines, and for design of novel second-generation vaccines. © 2006 Elsevier B.V. All rights reserved.

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Childcare workers play a significant role in the learning and development of children in their care. This has major implications for the training of workers. Under new reforms of the childcare industry the Australian government now requires all workers to obtain qualifications from a vocational education and training provider (eg. Technical and Further Education) or university. Effective models of employment-based training are critical to provide training to highly competent workers. This paper presents findings from a study that examined current and emerging models of employment-based training in the childcare sector, particularly at the Diploma level. Semi-structured interviews were conducted with a sample of 16 participants who represented childcare directors, employers, and workers located in childcare services in urban, regional and remote locations in the State of Queensland. The study proposes a ‘best-fit’ employment-based training approach that is characterised by a compendium of five models instead of a ‘one size fits all’. Issues with successful implementation of the EBT models are also discussed

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This article examines the continued relevance of the 16-19 business education curriculum in the UK, stimulated by doubts expressed by Thomas (1996), over its continued relevance. We express a concern that business education needs, but is struggling, to respond to significant societal shifts in consumption and production strategies that do not sit easily within traditional theories of business practice currently underpinning 16-19 business education. We examine firstly, the extent to which a formal body of knowledge couched in a modernist discourse of facts and objectivity can cope with the changing and fluid developments in much current business practice that is rooted in the cultural and symbolic. Secondly, the extent to which both academic and vocational competences provide the means for students to develop a framework of critical understanding that can respond effectively to rapidly changing business environments.Findings are based on research conducted jointly by the University of Manchester and the Manchester Institute for Popular Culture at Manchester Metropolitan University. The growth of dynamism of the cultural industries sector - largely micro-businesses and small and medium sized enterprises (SMEs) -encapsulates forms of business knowledge, business language and business practice which may not immediately fit with the models provided within business education. Results suggest increasingly reflexive forms of consumption being met by similarly reflexive and flexible modes of production.Our evidence suggests that whilst modernist business knowledge is often the foundation for many 16-19 business education courses, these programmes of study/training do not usually reflect the activities of SME and micro-business practitioners in the cultural industries. Given the importance of cultural industries in terms of the production strategies required to meet increasingly reflexive markets, it is suggested that there may be a need to incorporate a postmodern approach to the current content and pedagogy; one that is contextual, cultural and discursive.

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The mineral reevesite and the cobalt substituted reevesite have been synthesised. The d(003) spacings of the minerals ranged from 7.54 to 7.95 Å. The maximum d(003) value occurred at around Ni:Co 0.4:0.6. This maximum in interlayer distance is proposed to be due to a greater number of carbonate anions and water molecules intercalated into the structure. The stability of the reevesite and cobalt doped reevesite was determined by thermogravimetric analysis. The maximum temperature of the reevesite occurs for the unsubstituted reevesite and is around 220°C. The effect of cobalt substitution results in a decrease in thermal stability of the reevesites. Four thermal decomposition steps are observed and are attributed to dehydration, dehydroxylation and decarbonation, decomposition of the formed carbonate and oxygen loss at ~807 °C. A mechanism for the thermal decomposition of the reevesite and the cobalt substituted reevesite is proposed.

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We have successfully synthesized hydrotalcites (HTs) contg. calcium, which are naturally occurring minerals. Insight into the unique structure of HTs has been obtained using a combination of X-ray diffraction (XRD) as well as IR and Raman spectroscopies. Calcium-contg. hydrotalcites (Ca-HTs) of the formula Ca4Al2(CO3)(OH)12·4H2O (2:1 Ca-HT) to Ca8Al2(CO3)(OH)20· 4H2O (4:1 Ca-HT) have been successfully synthesized and characterised by XRD and Raman spectroscopy. XRD has shown that 3:1 calcium HTs have the largest interlayer distance. Raman spectroscopy complemented with selected IR data has been used to characterize the synthesized Ca-HTs. The Raman bands obsd. at around 1086 and 1077 cm-1 were attributed to the ν1 sym. stretching modes of the (CO32-) units of calcite and carbonate intercalated into the HT interlayer. The corresponding ν3 CO32- antisym. stretching modes are found at around 1410 and 1475 cm-1.

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Previous literature has focused on the need for support of undergraduate nursing students during clinical placements. Little is known about the support provided by employers for registered nurses (RNs) who pursue further education. This study sought to identify and describe the types, levels and perceived need for support in the workplace for RNs as they undertake further postgraduate nursing study by distance education (DE).Using an exploratory descriptive design a self-report questionnaire was distributed to a convenient sample of 270 RNs working in one acute care public hospital in Tasmania, Australia.92 questionnaires (response rate 34%) were returned with 26 (28%) reporting being currently enrolled in further study by DE and a further 50 (54)% of RNs planning future study. Results revealed that 100% of participants with a Masters degree completed this by DE. There were differences between the support sought by RNs to that offered by employers, and 16 (34%) who had done or were currently doing DE study, received no support to undertake DE. There was an overwhelming desire by RNs for support; 87 (94%), with a majority believing some support should be mandatory 76 (83%).This study may encourage employers to introduce structured support systems that will actively assist nurses to pursue further study. © 2010.

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This article investigates the complex phenomenon of major gift giving to charitable institutions. Drawing on empirical evidence from interviews with 16 Australian major donors (who gave a single gift of at least AU$10,000 in 2008 or 2009), we seek to better understand donor expectations and (dis)satisfaction. Given growing need for social services, and the competition among nonprofit organisations (NPOs) to secure sustainable funding, this research is particularly timely. Currently, little is known about major donors’ expectations, wants and needs. Equity theory, with the concept of reciprocity at its core, was found to provide a useful framework for understanding these phenomena. A model of equitable major gift relationships was developed from the data, which portrays balanced relationships and identifies potential areas of dissatisfaction for major donors. We conclude by offering suggestions for NPOs seeking to understand the complexities of major gift relationships, with practical implications for meeting donors’ needs.

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Virus-like particle-based vaccines for high-risk human papillomaviruses (HPVs) appear to have great promise; however, cell culture-derived vaccines will probably be very expensive. The optimization of expression of different codon-optimized versions of the HPV-16 L1 capsid protein gene in plants has been explored by means of transient expression from a novel suite of Agrobacterium tumefaciens binary expression vectors, which allow targeting of recombinant protein to the cytoplasm, endoplasmic reticulum (ER) or chloroplasts. A gene resynthesized to reflect human codon usage expresses better than the native gene, which expresses better than a plant-optimized gene. Moreover, chloroplast localization allows significantly higher levels of accumulation of L1 protein than does cytoplasmic localization, whilst ER retention was least successful. High levels of L1 (>17% total soluble protein) could be produced via transient expression: the protein assembled into higher-order structures visible by electron microscopy, and a concentrated extract was highly immunogenic in mice after subcutaneous injection and elicited high-titre neutralizing antibodies. Transgenic tobacco plants expressing a human codon-optimized gene linked to a chloroplast-targeting signal expressed L1 at levels up to 11% of the total soluble protein. These are the highest levels of HPV L1 expression reported for plants: these results, and the excellent immunogenicity of the product, significantly improve the prospects of making a conventional HPV vaccine by this means. © 2007 SGM.

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A Tobacco mosaic virus (TMV)-derived vector was used to express a native Human papillomavirus type 16 (HPV-16) L1 gene in Nicotiana benthamiana by means of infectious in vitro RNA transcripts inoculated onto N. benthamiana plants. HPV-16 L1 protein expression was quantitated by enzyme-linked immunosorbent assays (ELISA) after concentration of the plant extract. We estimated that the L1 product yield was 20-37 μg/kg of fresh leaf material. The L1 protein in the concentrated extract was antigenically characterised using the neutralising and conformation-specific Mabs H16:V5 and H16:E70, which bound to the plant-produced protein. Particles observed by transmission electron microscopy were mainly capsomers but virus-like particles (VLPs) similar to those produced in other systems were also present. Immunisation of rabbits with the concentrated plant extract induced a weak immune response. This is the first report of the successful expression of an HPV L1 gene in plants using a plant virus vector. © 2006 Elsevier B.V. All rights reserved.

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Human papillomaviruses (HPVs) are obligate epithelial pathogens and typically cause localized mucosal infections. We therefore hypothesized that T-cell responses to HPV antigens would be greater at sites of pathology than in the blood. Focusing on HPV-16 because of its association with cervical cancer, the magnitude of HPV-specific T-cell responses at the cervix was compared with those in the peripheral blood by intracellular cytokine staining following direct ex vivo stimulation with both virus-like particles assembled from the major capsid protein L1, and the major HPV oncoprotein, E7. We show that both CD4 + and CD8 + T cells from the cervix responded to the HPV-16 antigens and that interferon-γ (IFN-γ) production was HPV type-specific. Comparing HPV-specific T-cell IFN-γ responses at the cervix with those in the blood, we found that while CD4 + and CD8 + T-cell responses to L1 were significantly correlated between compartments (P = 0.02 and P = 0.05, respectively), IFN-γ responses in both T-cell subsets were significantly greater in magnitude at the cervix than in peripheral blood (P = 0.02 and P = 0.003, respectively). In contrast, both CD4 + and CD8 + T-cell IFN-γ responses to E7 were of similar magnitude in both compartments and CD8 + responses were significantly correlated between these distinct immunological compartments (P = 0.04). We therefore show that inflammatory T-cell responses against L1 (but not E7) demonstrate clear compartmental bias and the magnitude of these responses do reflect local viral replication but that correlation of HPV-specific responses between compartments indicates their linkage.