61 resultados para Tumour samples


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This study assessed the degree of equivalence between paper and Internet administration of three measures of panic and agoraphobia-related cognition and behavior: Body Sensations Questionnaire (BSQ), Agoraphobic Cognitions Questionnaire (ACQ), and Mobility Inventory (MI). Participants were 110 people with panic disorder who had registered for an Internet-based treatment program in Sweden (n = 54) or Australia (n = 56). Participants were randomly assigned to complete the questionnaires via the differing administration formats in a counterbalanced order. Results showed broadly equivalent psychometric properties across administrations, with strong significant intraclass correlations between them, and comparable Cronbach's alpha coefficients. A significant mean difference between administration formats was found for the BSQ only. In contrast to previous research, Internet administration did not generate higher scores than paper administration. No effect was found for order of administration. The findings suggest that each questionnaire can be validly administered via the Internet and used with confidence.

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The performance of a new mesozooplankton sampler, the U-Tow, was compared to that of the traditional WP2 net. The U-Tow significantly underestimated species abundance, but gave a very good representation of species composition and community size structure. WP2 net samples could be used to calibrate the U-Tow, allowing absolute abundance to be determined. It is recommended that the U-Tow, in its current configuration, be used in conjunction with WP2 net samples to give measures of abundance, or as a tool to identify areas of change in plankton communities.

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Whilst a multitude of techniques have been employed to study the biology of tumour tissue and its response to chemotherapeutic reagents, most current methodologies do not capture the sophistication of the in vivo environment. Microfluidics however offers the ability to maintain and interrogate primary tissue samples in an environment with biomimetic flow characteristics. In this study head and neck squamous cell carcinoma (HNSCC) tumour biopsies have been used to investigate the performance of a microfluidic device for generating clinically-useful information. The response of fresh and cryogenically-frozen primary HNSCC or metastatic lymph node samples to chemotherapy drugs (cisplatin, 5-flurouracil or docetaxel), alone and in combination, were monitored for both proliferation (water-soluble tetrazolium salt metabolism) and cell death biomarker release (lactate dehydrogenase, LDH) “off-chip”. The frozen tissue showed no significant difference in terms of either proliferation or LDH release in comparison with the matched fresh samples. Administration of all drugs caused cell death, in a dose-response manner, with the combination showing the greatest amount of cytotoxicity particularly at days 8 and 9; correlating well with published clinical data. The system described here offers an innovative method for studying the tumour microenvironment in vitro and, through incorporation of relevant analytical modules, provides the basis of a pre-clinical device that can be used to define personalised treatment regimens.

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Urine is a preferred specimen for nucleic acid-based detection of sexually transmitted infections (STIs) but represents a challenge for microfluidic devices due to low analyte concentrations. We present an extraction methodology enabling rapid on-chip nucleic acid purification directly from clinically relevant sample volumes up to 1 ml and subsequent PCR amplification detection.

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Devil facial tumour disease (DFTD) is a fatal contagious cancer that has decimated Tasmanian devil populations. The tumour has spread without invoking immune responses, possibly due to low levels of Major Histocompatibility Complex (MHC) diversity in Tasmanian devils. Animals from a region in north-western Tasmania have lower infection rates than those in the east of the state. This area is a genetic transition zone between sub-populations, with individuals from north-western Tasmania displaying greater diversity than eastern devils at MHC genes, primarily through MHC class I gene copy number variation. Here we test the hypothesis that animals that remain healthy and tumour free show predictable differences at MHC loci compared to animals that develop the disease.

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Thousands of blood samples taken from Australia’s indigenous people lie in institutional freezers of the global North, the legacy of a half-century of scientific research. Since those collections were assembled, standards of ethical research practice have changed dramatically, leaving some samples in a state of dormancy. While some European and American collections are still actively used for genetic research, this practice is viewed as unethical by most Australian genetic researchers, who have closer relationships with indigenous Australians and postcolonial politics. For collections to be used ethically, they require a ‘guardian’ who has an ongoing and documented relationship with the donors, so that consent to further studies on samples can be negotiated. This affective and bureaucratic network generates ‘ethical biovalue’ such that a research project can satisfy Australian ethical review. I propose in this article that without ethical biovalue, collections become ‘orphan’ DNA, divorced from a guardian and often difficult to trace to their sources. Such samples are both orphaned and functionally sterile, unable to produce data, scientific articles, knowledge or prestige. This article draws on an ethnographic study of genetic researchers who are working in indigenous communities across Australia. I present tales of researchers’ efforts to generate ethical biovalue and their fears for succession; fears that extend to threats to destroy samples rather than see them orphaned, or worse, fall into the wrong hands. Within these material and affective  networks, indigenous DNA morphs from biological sample to sacred object to political time bomb.