964 resultados para Comparative genomics
Resumo:
In our laboratory, we have developed methods in real-time detection and quantitative-polymerase chain reaction (Q-PCR) to analyse the relative levels of gene expression in post mortem brain tissues. We have then applied this method to examine differences in gene activity between normal white matter (NWM) and plaque tissue from multiple sclerosis (MS) patients. Genes were selected based on their association with pathology and through identification by previously conducted global gene expression analysis. Plaque tissue was obtained from secondary progressive (SP) patients displaying chronic active, as well as acute pathologies; while NWM from the same location was obtained from age- and sex-matched controls (normal patients). In this study, we used both SYBR Green I supplementation and commercially available mixes to assess both comparative and absolute levels of gene activity. The results of both methods compared favourably for four of the five genes examined (P < 0.05, Pearsons), while differences in gene expression between chronic active and acute pathologies were also identified. For example, a >50-fold increase in osteopontin (Spp1) and inositol 1-4-5 phosphate 3 kinase B (Itpkb) levels in acute plaques contrasted with the 5-fold or less increase in chronic active plaques (P < 0.05, unpaired t test). By contrast, there was no significant difference in the levels of the MS marker and calcium-dependent protease (Calpain, Capns1) in MS plaque tissue. In summary, Q-PCR analysis using SYBR Green I has allowed us to economically obtain what may be clinically significant information from small amounts of the CNS, providing an opportunity for further clinical investigations.
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OBJECTIVE: To identify chromosomal copy numbers of frequent genetic aberrations within squamous cell carcinomas (SCCs) and solar keratoses (SKs), and provide further evidence to support or challenge current dogma concerning the relationship between these lesions. DESIGN: Retrospective analysis of genetic aberrations in DNA from SK and SCC biopsy specimens by comparative genomic hybridization. SETTING: University-based research laboratory in Queensland, Australia. PATIENTS: Twenty-two biopsy specimens from patients with diagnosed SKs (n = 7), cutaneous SCCs (n = 10), or adjoining lesions (n = 5). MAIN OUTCOME MEASURES: Identification of frequent genetic aberrations both specific to SK and SCC and shared by these lesions to investigate their clonal relationship. RESULTS: Shared genomic imbalances were identified in SK and SCC. Frequent gains were located at chromosome arms 3q, 17q, 4p, 14q, Xq, 5p, 9q, 8q, 17p, and 20q, whereas shared regional losses were observed at 9p, 3p, 13q, 17p, 11p, 8q, and 18p. Significant loss of 18q was observed only in SCC lesions. CONCLUSIONS: Our results demonstrate that numerous chromosomal aberrations are shared by the 2 lesions, suggesting a clonal relationship between SK and SCC. Additionally, the genomic loss of 18q may be a significant event in SK progression to SCC. Finally, the type and frequency of aberrations suggests a common mode of tumorigenesis in SCC-derived tumors.
Resumo:
In an attempt to define genomic copy number changes associated with the development of basal cell carcinoma, we investigated 15 sporadic tumors by comparative genomic hybridization. With the incorporation of tissue microdissection and degenerate oligonucleotide primed-polymerase chain reaction we were able to isolate, and then universally amplify, DNA from the tumor type. This combined approach allows the investigation of chromosomal imbalances within a histologically distinct region of tissue. Using comparative genomic hybridization we have observed novel and recurrent chromosomal gains at 6p (47%), 6q (20%), 9p (20%), 7 (13%), and X (13%). In addition comparative genomic hybridization revealed regional loss on 9q in 33% of tested tumors encompassing 9q22.3 to which the putative tumor suppressor gene, Patched, has been mapped. The deletion of Patched has been indicated in the development of hereditary and sporadic basal cell carcinomas. The identification of these recurrent genetic aberrations suggests that basal cell carcinomas may not be as genetically stable as previously thought. Further investigation of these regions may lead to the identification of other genes responsible for basal cell carcinoma formation.
Resumo:
The ubiquitous chemical messenger molecule nitric oxide (NO) has been implicated in a diverse range of biological activities including neurotransmission, smooth muscle motility and mediation of nociception. Endogenous synthesis of NO by the neuronal isoform of the nitric oxide synthase gene family has an essential role within the central and peripheral nervous systems in addition to the autonomic innervation of cerebral blood vessels. To investigate the potential role of NO and more specifically the neuronal nitric oxide synthase (nNOS) gene in migraine susceptibility, we investigated two microsatellite repeat variants residing within the 5′ and 3′ regions of the nNOS gene. Population genomic evaluation of the two nNOS repeat variants indicated significant linkage disequilibrium between the two loci. Z-DNA conformational sequence structures within the 5′ region of the nNOS gene have the potential to enhance or repress gene promoter activity. We suggest that genetic analysis of this 5′ repeat variant is the more functional variant expressing gene wide information that could affect endogenous NO synthesis and potentially result in diseased states. However, no association with migraine (with or without aura) was seen in our extensive case-control cohort (n = 579 affected with matched controls), when both the 5′ and 3′ genetic variants were investigated.
Resumo:
Electricity is the cornerstone of modern life. It is essential to economic stability and growth, jobs and improved living standards. Electricity is also the fundamental ingredient for a dignified life; it is the source of such basic human requirements as cooked food, a comfortable living temperature and essential health care. For these reasons, it is unimaginable that today's economies could function without electricity and the modern energy services that it delivers. Somewhat ironically, however, the current approach to electricity generation also contributes to two of the gravest and most persistent problems threatening the livelihood of humans. These problems are anthropogenic climate change and sustained human poverty. To address these challenges, the global electricity sector must reduce its reliance on fossil fuel sources. In this context, the object of this research is twofold. Initially it is to consider the design of the Renewable Energy (Electricity) Act 2000 (Cth) (Renewable Electricity Act), which represents Australia's primary regulatory approach to increase the production of renewable sourced electricity. This analysis is conducted by reference to the regulatory models that exist in Germany and Great Britain. Within this context, this thesis then evaluates whether the Renewable Electricity Act is designed effectively to contribute to a more sustainable and dignified electricity generation sector in Australia. On the basis of the appraisal of the Renewable Electricity Act, this thesis contends that while certain aspects of the regulatory regime have merit, ultimately its design does not represent an effective and coherent regulatory approach to increase the production of renewable sourced electricity. In this regard, this thesis proposes a number of recommendations to reform the existing regime. These recommendations are not intended to provide instantaneous or simple solutions to the current regulatory regime. Instead, the purpose of these recommendations is to establish the legal foundations for an effective regulatory regime that is designed to increase the production of renewable sourced electricity in Australia in order to contribute to a more sustainable and dignified approach to electricity production.
Resumo:
The thesis is a comparative study of ICTs and Internet use of Australian and Malaysian early childhood teachers in terms of their personal and professional comfort with ICTs, pedagogical beliefs, and their reported classroom practice. The study discovered teachers from both countries as relatively comfortable with digital technologies and the Internet, with most teachers held positive beliefs about ICT usage. The structural barriers in classrooms include lack of Internet access and the wide gap that exists between teachers’ positive beliefs and classroom practice. The study suggests the need for strategic and targeted professional development for teachers.
Resumo:
OBJECTIVE: To optimize the animal model of liver injury that can properly represent the pathological characteristics of dampness-heat jaundice syndrome of traditional Chinese medicine. METHODS: The liver injury in the model rat was induced by alpha-naphthylisothiocyanate (ANIT) and carbon tetrachloride (CCl(4) ) respectively, and the effects of Yinchenhao Decoction (, YCHD), a proved effective Chinese medical formula for treating the dampness-heat jaundice syndrome in clinic, on the two liver injury models were evaluated by analyzing the serum level of alanine aminotransferase (ALT), asparate aminotransferase (AST), alkaline phosphatase (ALP), malondialchehyche (MDA), total bilirubin (T-BIL), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) as well as the ratio of liver weight to body weight. The experimental data were analyzed by principal component analytical method of pattern recognition. RESULTS: The ratio of liver weight to body weight was significantly elevated in the ANIT and CCl(4) groups when compared with that in the normal control (P<0.01). The contents of ALT and T-BIL were significantly higher in the ANIT group than in the normal control (P<0.05,P<0.01), and the levels of AST, ALT and ALP were significantly elevated in CCl(4) group relative to those in the normal control P<0.01). In the YCHD group, the increase in AST, ALT and ALP levels was significantly reduced (P<0.05, P<0.01), but with no significant increase in serum T-BIL. In the CCl(4) intoxicated group, the MDA content was significantly increased and SOD, GSH-PX activities decreased significantly compared with those in the normal control group, respectively (P<0.01). The increase in MDA induced by CCl(4) was significantly reduced by YCHD P<0.05). CONCLUSION: YCHD showed significant effects on preventing liver injury progression induced by CCl(4), and the closest or most suitable animal model for damp-heat jaundice syndrome may be the one induced by CCl(4).
Resumo:
Purpose - Cultural issues in the construction industry have attracted growing attention from both practitioners and academia. However, there are few studies on culture issues at the project level. The influence of project culture has not traditionally been on the research radar. This research aims to investigate the impacts of project culture on the performance of construction projects. Design/methodology/approach - A case study approach, utilising questionnaire surveys, in-depth interviews and review of project documents, was employed to investigate project culture and its associated impacts in two major hospital projects. Findings - The results indicated that project culture played an important role in achieving harmonious relationships between project participants and better project outcomes in terms of schedule, functionality, satisfaction with the process, satisfaction with the relationships, environmental issues addressed commercial success, further business opportunities and overall performance. Case 1 outperformed Case 2 in these performance indicators. Similarly, it became clear that the project’s culture should be developed from the outset and sustained during the project period. Furthermore, it was also highlighted that the project culture should be translated to all levels of the supply chain i.e. sub-contractors and suppliers. Practical implications – The findings enabled the client to understand the role of project culture and actively commit towards the development and maintenance of the project culture from very early on. It also helps project teams to understand how to deal with cultural issues at the project level. Originality/value- This study is one of limited empirical studies that offer in-depth insights of how project culture affects the performance of construction projects. It is also the first study of hospital projects on the research topic.
Resumo:
This thesis commences with the proposition that the first limb of the doctrine of privity causes injustice to third party beneficiaries in Malaysia, particularly in commercial contracts. The doctrine of privity has been the subject of criticism by the judiciary and academic commentators in common law jurisdictions, mainly directed at the first limb of the doctrine, whereby only parties to a contract can sue and be sued. The first limb prevents a third party from enforcing benefits conferred on them by those contracts thereby resulting in third parties suffering loss and injustice to those parties. In several common law countries, such as England, Australia, New Zealand and Singapore, legislative reform of the doctrine has occurred. The legislative reform has abrogated to a significant extent the doctrine of privity in commercial contracts. Malaysia is a common law country, where the doctrine of privity is still applied to contracts. An analysis of Malaysian case law demonstrates that the most affected third party beneficiaries are those seeking to enforce insurance and construction contracts. While a small number of other third parties to commercial contracts, such as agreements to pay for work done, sale and purchase agreements and tenancy agreements are also affected, the detriment is not as significant. As a consequence, this thesis focuses primarily on the impact of the doctrine of privity on commercial contracts in the areas of insurance and construction in Malaysia The thesis aims to recommend appropriate reforms to address the injustices arising from the privity doctrine for third parties seeking to obtain the benefit of insurance and construction contracts, which may also benefit third parties to other types of commercial contracts. While the Malaysian insurance, consumer protection, negotiable instruments and agency laws allow third party beneficiaries to enforce benefits in contracts, the rights are found to be inadequate. As not all third parties seeking to enforce an insurance or construction contract can rely upon the legislation, the injustice arising from the doctrine of privity remains and needs to be addressed. To achieve this aim, a comparative analysis of the rights of third party beneficiaries under insurance and construction contracts in Malaysia, Australia and England is undertaken. The results of the analysis are used to identify appropriate elements for a legislative framework guided by the three essential criteria for effective law reform developed in the thesis. The three criteria are certainty, public interest and justice. The thesis recommends first the enactment of general legislation applicable to all commercial contracts including insurance contracts. Secondly, the thesis recommends specific targeted legislation to address the injustice faced by third party beneficiaries in construction contracts.
Resumo:
Over the last decade advanced composite materials, like carbon fibre reinforced polymer (CFRP), have increasingly been used in civil engineering infrastructure. The benefits of advanced composites are rapidly becoming evident. This paper focuses on the comparative performance of steel and concrete members retrofitted by carbon fibre reinforced polymers. The objective of this work is a systematic assessment and evaluation of the performance of CFRP for both the concrete and steel members available in the technical literature. Existing empirical and analytical models were studied. Comparison is made with respect to failure mode, bond characteristics, fatigue behaviour, durability, corrosion, load carrying capacity and force transfer. It is concluded that empirical expressions for the concrete-CFRP composite are not readily suited for direct use in the steel-CFRP composite. This paper identifies some of the major issues that need further investigation.
Resumo:
Plant and animal microRNAs (miRNAs) are evolutionarily ancient small RNAs, ∼19-24 nucleotides in length, that are generated by cleavage from larger highly structured precursor molecules. In both plants and animals, miRNAs posttranscriptionally regulate gene expression through interactions with their target mRNAs, and these targets are often genes involved with regulating key developmental events. Despite these similarities, plant and animal miRNAs exert their control in fundamentally different ways. Generally, animal miRNAs repress gene expression by mediating translational attenuation through (multiple) miRNA-binding sites located within the 3′ untranslated region of the target gene. In contrast, almost all plant miRNAs regulate their targets by directing mRNA cleavage at single sites in the coding regions. These and other differences suggest that the two systems may have originated independently, possibly as a prerequisite to the development of complex body plans. © Springer-Verlag 2005.
Resumo:
Business process analysis and process mining, particularly within the health care domain, remain under-utilised. Applied research that employs such techniques to routinely collected, health care data enables stakeholders to empirically investigate care as it is delivered by different health providers. However, cross-organisational mining and the comparative analysis of processes present a set of unique challenges in terms of ensuring population and activity comparability, visualising the mined models and interpreting the results. Without addressing these issues, health providers will find it difficult to use process mining insights, and the potential benefits of evidence-based process improvement within health will remain unrealised. In this paper, we present a brief introduction on the nature of health care processes; a review of the process mining in health literature; and a case study conducted to explore and learn how health care data, and cross-organisational comparisons with process mining techniques may be approached. The case study applies process mining techniques to administrative and clinical data for patients who present with chest pain symptoms at one of four public hospitals in South Australia. We demonstrate an approach that provides detailed insights into clinical (quality of patient health) and fiscal (hospital budget) pressures in health care practice. We conclude by discussing the key lessons learned from our experience in conducting business process analysis and process mining based on the data from four different hospitals.
Resumo:
The progress of technology has led to the increased adoption of energy monitors among household energy consumers. While the monitors available on the market deliver real-time energy usage feedback to the consumer, the form of this data is usually unengaging and mundane. Moreover, it fails to address consumers with different motivations and needs to save and compare energy. This master‟s thesis project presents a study that seeks to inform design guidelines for differently motivated energy consumers. The focus of the research is on comparative feedback supported by a community of energy consumers. In particular, the discussed comparative feedback types are explanatory comparison, temporal self-comparison, norm comparison, one-on-one comparison and ranking, whereby the last three support exploring the potential of socialising energy-related feedback in social networking sites, such as Facebook. These feedback types were integrated in EnergyWiz – a mobile application that enables users to compare with their past performance, neighbours, contacts from social networking sites and other EnergyWiz users. The application was developed through a theory-driven approach and evaluated in personal, semi-structured interviews which provided insights on how motivation-related comparative feedback should be designed. It was also employed in expert focus group discussions which resulted in defining opportunities and challenges before mobile, social energy monitors. The findings have unequivocally shown that users with different motivations to compare and to conserve energy have different preferences for comparative feedback types and design. It was established that one of the most influential factors determining design factors is the people users compare to. In addition, the research found that even simple communication strategies in Facebook, such as wall posts and groups can contribute to engagement with energy conservation practices. The concept of mobility of the application was evaluated as positive since it provides place and time-independent access to the energy consumption data.