496 research outputs found

    Clinical validity assessment of a breast cancer risk model combining genetic and clinical information

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    _Background:_ The extent to which common genetic variation can assist in breast cancer (BCa) risk assessment is unclear. We assessed the addition of risk information from a panel of BCa-associated single nucleotide polymorphisms (SNPs) on risk stratification offered by the Gail Model.

_Methods:_ We selected 7 validated SNPs from the literature and genotyped them among white women in a nested case-control study within the Women’s Health Initiative Clinical Trial. To model SNP risk, previously published odds ratios were combined multiplicatively. To produce a combined clinical/genetic risk, Gail Model risk estimates were multiplied by combined SNP odds ratios. We assessed classification performance using reclassification tables and receiver operating characteristic (ROC) curves. 

_Results:_ The SNP risk score was well calibrated and nearly independent of Gail risk, and the combined predictor was more predictive than either Gail risk or SNP risk alone. In ROC curve analysis, the combined score had an area under the curve (AUC) of 0.594 compared to 0.557 for Gail risk alone. For reclassification with 5-year risk thresholds at 1.5% and 2%, the net reclassification index (NRI) was 0.085 (Z = 4.3, P = 1.0×10^-5^). Focusing on women with Gail 5-year risk of 1.5-2% results in an NRI of 0.195 (Z = 3.8, P = 8.6×10^−5^).

_Conclusions:_ Combining clinical risk factors and validated common genetic risk factors results in improvement in classification of BCa risks in white, postmenopausal women. This may have implications for informing primary prevention and/or screening strategies. Future research should assess the clinical utility of such strategies.
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    Optical Imaging of the Nanoscale Structure and Dynamics of Biological Membranes

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    Biological membranes serve as the fundamental unit of life, allowing the compartmentalization of cellular contents into subunits with specific functions. The bilayer structure, consisting of lipids, proteins, small molecules, and sugars, also serves many other complex functions in addition to maintaining the relative stability of the inner compartments. Signal transduction, regulation of solute exchange, active transport, and energy transduction through ion gradients all take place at biological membranes, primarily with the assistance of membrane proteins. For these functions, membrane structure is often critical. The fluid-mosaic model introduced by Singer and Nicolson in 1972 evokes the dynamic and fluid nature of biological membranes.(1) According to this model, integral and peripheral proteins are oriented in a viscous phospholipid bilayer. Both proteins and lipids can diffuse laterally through the two-dimensional structure. Modern experimental evidence has shown, however, that the structure of the membrane is considerably more complex; various domains in the biological membranes, such as lipid rafts and confinement regions, form a more complicated molecular organization. The proper organization and dynamics of the membrane components are critical for the function of the entire cell. For example, cell signaling is often initiated at biological membranes and requires receptors to diffuse and assemble into complexes and clusters, and the resulting downstream events have consequences throughout the cell. Revealing the molecular level details of these signaling events is the foundation to understanding numerous unsolved questions regarding cellular life

    The New ‘Hidden Abode’: Reflections on Value and Labour in the New Economy

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    In a pivotal section of Capital, volume 1, Marx (1976: 279) notes that, in order to understand the capitalist production of value, we must descend into the ‘hidden abode of production’: the site of the labour process conducted within an employment relationship. In this paper we argue that by remaining wedded to an analysis of labour that is confined to the employment relationship, Labour Process Theory (LPT) has missed a fundamental shift in the location of value production in contemporary capitalism. We examine this shift through the work of Autonomist Marxists like Hardt and Negri, Lazaratto and Arvidsson, who offer theoretical leverage to prize open a new ‘hidden abode’ outside employment, for example in the ‘production of organization’ and in consumption. Although they can open up this new ‘hidden abode’, without LPT's fine-grained analysis of control/resistance, indeterminacy and structured antagonism, these theorists risk succumbing to empirically naive claims about the ‘new economy’. Through developing an expanded conception of a ‘new hidden abode’ of production, the paper demarcates an analytical space in which both LPT and Autonomist Marxism can expand and develop their understanding of labour and value production in today's economy. </jats:p

    Labour supply and skills demands in fashion retailing

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    If, as Adam Smith once famously suggested, Britain was a nation of shopkeepers then it is now a nation of shopworkers. Retail is now a significant part of the UK economy, accounting for £256 billion in sales and one-third of all consumer spending (Skillsmart, 2007). It is the largest private sector employer in the UK, employing 3m workers, or 1 in 10 of the working population. For future job creation in the UK economy retail is also similarly prominent and the sector is expected to create a further 250,000 jobs to 2014 (Skillsmart, 2007). The centrality of retail to economic success and job creation is apparent in other advanced economies. For example, within the US, retail sales is the occupation with the largest projected job growth in the period 2004-2014 (Gatta et al., 2009) and in Australia retail accounts for 1 in 6 workers (Buchanan et al., 2003). Within the UK these workers are employed in approximately 290,000 businesses, encompassing large and small organizations and also a number of sub-sectors. This variance suggests that retail should not be regarded as homogenous in its labour demands. Hart et al. (2007) note how skill requirements and the types of workers employed may differ across the sector. This chapter further opens up this point, providing an analysis of the labour supply and skills demands for the sub-sectors of clothing, footwear and leather goods, which are described by Skillsmart (2007: 48) as being 'significant categories in UK retailing'

    Top-down and bottom-up approach to competence management implementation: A case of two central banks Abordagem top-down (de cima para baixo) e bottom-up (de baixo para cima) para a implementação de gestão de competências: O caso de dois bancos centrais

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    Abstract The primary aim of this paper is to evaluate the contribution that competence based approaches to staff management can and ought to make to the overall effectiveness of organisations. The importance of competencies and their proper management is broadly acknowledged in the literature, and the first part of the paper is a literature review. This is followed with a comparison of the design and implementation of two competence management projects that were introduced in two central banks, one of a western European nation, and the other of a central European nation. There is a brief presentation of two fundamental approaches to competence management implementation in organization (top-down (directive) and bottom-up (participative)), and this is juxtaposed with the actual implementation of competence management model that took place in two central banks. What ensues from the comparison is the identification of potential threats to the implementation of competence management models in organizations, accompanied by suggestions on how to counteract them. Keywords: Strategic HRM, competencies, competence management, organisation development, HR development strategies. Resumo O objetivo principal deste trabalho é avaliar o contributo que as abordagens baseadas nas competências na gestão do pessoal pode e deve dar para a eficácia global das organizações. A primeira parte do artigo faz uma revisão da literatura, na qual a importância das competências e da sua correta gestão é amplamente reconhecida. Segue-se uma comparação entre o desenho e implementação de dois projetos de gestão de competências que foram introduzidas em dois bancos centrais, um de um país da Europa Ocidental e outro de um país da Europa Central. Há uma breve apresentação de duas abordagens fundamentais para a implementação da gestão de competências numa organização (topdown (diretiva) e bottom-up (participativa)), sendo isto justaposto com a implementação do modelo de gestão de competências que ocorreu em dois bancos centrais

    Colorectal cancer in relation to postmenopausal estrogen and estrogen plus progestin in the Women’s Health Initiative clinical trial and observational study

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    Background: Colorectal cancer incidence was reduced among women assigned to active treatment in the Women’s Health Initiative (WHI) estrogen plus progestin randomized trial, but the interpretation was obscured by an associated later stage of diagnosis. In contrast the estrogen-alone trial showed no incidence reduction or differential stage at diagnosis. Here, data from the WHI observational study are considered, in conjunction with colorectal cancer mortality data from the hormone therapy trials, in an attempt to clarify postmenopausal hormone therapy effects. Participants and Methods: Postmenopausal women aged 50-79 at WHI enrollment. Estrogen-alone analyses include 21,552 and 10,739 women who were post-hysterectomy from the observational study and clinical trial respectively. Estrogen plus progestin analyses include 32,084 and 16,608 observational study and clinical trial women with uterus. Colorectal cancers were verified by central medical and pathology report review. Results: Hazard ratios (95% confidence intervals) from the WHI observational study were 0.80 (0.53 to 1.20) for estrogen and 1.15 (0.74 to 1.79) for estrogen plus progestin, with respectively 168 and 175 women diagnosed with colorectal cancer. Delayed diagnosis with estrogen plus progestin is not evident in the observational study. No protective effect on colorectal cancer mortality in the estrogen plus progestin trial is seen over an 8-year intervention and follow-up period. Conclusion: Hazard ratio patterns in the WHI clinical trial and observational study do not provide strong evidence of a clinically important colorectal cancer benefit with either estrogen-alone or estrogen plus progestin over 7-8 years of treatment and follow-up
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