21 research outputs found

    Advances in establishment and analysis of three-dimensional tumor spheroid-based functional assays for target validation and drug evaluation

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    There is overwhelming evidence that in vitro three-dimensional tumor cell cultures more accurately reflect the complex in vivo microenvironment than simple two-dimensional cell monolayers, not least with respect to gene expression profiles, signaling pathway activity and drug sensitivity. However, most currently available threedimensional techniques are time consuming and/or lack reproducibility; thus standardized and rapid protocols are urgently needed. To address this requirement, we have developed a versatile toolkit of reproducible three-dimensional tumor spheroid models for dynamic, automated, quantitative imaging and analysis that are compatible with routine high-throughput preclinical studies. Not only do these microplate methods measure three-dimensional tumor growth, but they have also been significantly enhanced to facilitate a range of functional assays exemplifying additional key hallmarks of cancer, namely cell motility and matrix invasion. Moreover, mutual tissue invasion and angiogenesis is accommodated by coculturing tumor spheroids with murine embryoid bodies within which angiogenic differentiation occurs. Highly malignant human tumor cells were selected to exemplify therapeutic effects of three specific molecularly-targeted agents: PI-103 (phosphatidylinositol-3-kinase (PI3K)- mammalian target of rapamycin (mTOR) inhibitor), 17-N-allylamino-17-demethoxygeldanamycin (17-AAG) (heat shock protein 90 (HSP90) inhibitor) and CCT130234 (in-house phospholipase C (PLC)g inhibitor). Fully automated analysis using a Celigo cytometer was validated for tumor spheroid growth and invasion against standard image analysis techniques, with excellent reproducibility and significantly increased throughput. In addition, we discovered key differential sensitivities to targeted agents between two-dimensional and three-dimensional cultures, and also demonstrated enhanced potency of some agents against cell migration/invasion compared with proliferation, suggesting their preferential utility in metastatic disease.: We have established and validated a suite of highly reproducible tumor microplate threedimensional functional assays to enhance the biological relevance of early preclinical cancer studies. We believe these assays will increase the translational predictive value of in vitro drug evaluation studies and reduce the need for in vivo studies by more effective triaging of compounds.This work was funded by The National Centre for the Replacement, Refinement and Reduction of Animals in Research (G1000121 ID no. 94513), Cancer Research UK (grant number C309/A8274), and by Red Tematica de Investigación Cooperativa en Cancer (RD06/0020/1022). We acknowledge NHS funding to the NIHR Biomedical Research Centre. MM is supported by a postdoctoral research contract (FIS, Program ‘Sara Borrell’, Instituto de Salud Carlos III), Ministerio de Ciencia e Innovación, Spain

    The emergence of new psychoactive substance (NPS) benzodiazepines: a review

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    The market for new psychoactive substances has increased markedly in recent years and there is now a steady stream of compounds appearing every year. Benzodiazepines consist of only a fraction of the total number of these compounds but their use and misuse has rapidly increased. Some of these benzodiazepines have only been patented, some of them have not been previously synthesised and the majority have never undergone clinical trials or tests. Despite their structural and chemical similarity, large differences exist between the benzodiazepines in their pharmacokinetic parameters and metabolic pathways and so they are not easily comparable. As benzodiazepines have been clinically used since the 1960s many analytical methods exist to quantify them in a variety of biological matrices and it is expected that these methods would also be suitable for the detection of benzodiazepines that are new psychoactive substances. Illicitly obtained benzodiazepines have been found to contain a wide range of compounds such as opiates which presents a problem since the use of them in conjunction with each other can lead to respiratory depression and death. The aim of this review is to collate the available information on these benzodiazepines and to provide a starting point for the further investigation of their pharmacokinetics which is clearly required

    Getting research into policy - Herpes simplex virus type-2 (HSV-2) treatment and HIV infection: international guidelines formulation and the case of Ghana

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    BACKGROUND: Observational epidemiological and biological data indicate clear synergies between Herpes simplex virus type 2 (HSV-2) and HIV, whereby HSV-2 enhances the potential for HIV acquisition or transmission. In 2001, the World Health Organization (WHO) launched a call for research into the possibilities of disrupting this cofactor effect through the use of antiherpetic therapy. A WHO Expert Meeting was convened in 2008 to review the research results. The results of the trials were mostly inconclusive or showed no impact. However, the WHO syndromic management treatment guidelines were modified to include acyclovir as first line therapy to treat genital ulcer disease on the basis of the high prevalence of HSV-2 in most settings, impact and cost-benefit of treatment on ulcer healing and quality of life among patients. METHODS: This paper examines the process through which the evidence related to HIV-HSV-2 interactions influenced policy at the international level and then the mechanism of international to national policy transfer, with Ghana as a case study. To better understand the context within which national policy change occurs, special attention was paid to the relationships between researchers and policy-makers as integral to the process of getting evidence into policy. Data from this study were then collected through interviews conducted with researchers, program managers and policy-makers working in sexual health/STI at the 2008 WHO Expert Meeting in Montreux, Switzerland, and in Accra, Ghana. RESULTS: The major findings of this study indicate that investigations into HSV-2 as a cofactor of HIV generated the political will necessary to reform HSV-2 treatment policy. Playing a pivotal role at both the international level and within the Ghanaian policy context were 'policy networks' formed either formally (WHO) or informally (Ghana) around an issue area. These networks of professionals serve as the primary conduit of information between researchers and policy-makers. Donor influence was cited as the single strongest impetus and impediment to policy change nationally. CONCLUSIONS: Policy networks may serve as the primary driving force of change in both international context and in the case of Ghana. Communication among researchers and policy-makers is critical for uptake of evidence and opportunities may exist to formalize policy networks and engage donors in a productive and ethical way

    Enhancing Europe’s global power: a scenario exercise with eight proposals

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    In the present context of intensifying competition between the major trading economies and potentially game-changing technological developments, the European Union is generally seen as the weaker party. Lacking the ‘hard power’ derived from military capabilities, it has laid claim to a ‘soft power’ of normative influence externally, yet even that is only partially utilised. Nor has Europe been able to exercise the power to coerce – ‘sharp power’ – commensurate with its economic weight as a trading bloc equivalent in size and reach to the US or China, its most prominent global competitors. How can Europe strengthen its position, and in what fields? Through a scenario exercise, we develop eight policy proposals aimed at countering Europe´s vulnerabilities and enabling it to assert its sharp and soft power more effectively. Specifically, we consider the feasibility, means and scope for their realisation. Together, they provide a transformative agenda for the EU’s position in the world

    Building health research systems to achieve better health

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    Health research systems can link knowledge generation with practical concerns to improve health and health equity. Interest in health research, and in how health research systems should best be organised, is moving up the agenda of bodies such as the World Health Organisation. Pioneering health research systems, for example those in Canada and the UK, show that progress is possible. However, radical steps are required to achieve this. Such steps should be based on evidence not anecdotes. Health Research Policy and Systems (HARPS) provides a vehicle for the publication of research, and informed opinion, on a range of topics related to the organisation of health research systems and the enormous benefits that can be achieved. Following the Mexico ministerial summit on health research, WHO has been identifying ways in which it could itself improve the use of research evidence. The results from this activity are soon to be published as a series of articles in HARPS. This editorial provides an account of some of these recent key developments in health research systems but places them in the context of a distinguished tradition of debate about the role of science in society. It also identifies some of the main issues on which 'research on health research' has already been conducted and published, in some cases in HARPS. Finding and retaining adequate financial and human resources to conduct health research is a major problem, especially in low and middle income countries where the need is often greatest. Research ethics and agenda-setting that responds to the demands of the public are issues of growing concern. Innovative and collaborative ways are being found to organise the conduct and utilisation of research so as to inform policy, and improve health and health equity. This is crucial, not least to achieve the health-related Millennium Development Goals. But much more progress is needed. The editorial ends by listing a wide range of topics related to the above priorities on which we hope to feature further articles in HARPS and thus contribute to an informed debate on how best to achieve such progress

    Contribution mapping: a method for mapping the contribution of research to enhance its impact.

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    Background: At a time of growing emphasis on both the use of research and accountability, it is important for research funders, researchers and other stakeholders to monitor and evaluate the extent to which research contributes to better action for health, and find ways to enhance the likelihood that beneficial contributions are realized. Past attempts to assess research 'impact' struggle with operationalizing 'impact', identifying the users of research and attributing impact to research projects as source. In this article we describe Contribution Mapping, a novel approach to research monitoring and evaluation that aims to assess contributions instead of impacts. The approach focuses on processes and actors and systematically assesses anticipatory efforts that aim to enhance contributions, so-called alignment efforts. The approach is designed to be useful for both accountability purposes and for assisting in better employing research to contribute to better action for health.Methods: Contribution Mapping is inspired by a perspective from social studies of science on how research and knowledge utilization processes evolve. For each research project that is assessed, a three-phase process map is developed that includes the main actors, activities and alignment efforts during research formulation, production and knowledge extension (e.g. dissemination and utilization). The approach focuses on the actors involved in, or interacting with, a research project (the linked actors) and the most likely influential users, who are referred to as potential key users. In the first stage, the investigators of the assessed project are interviewed to develop a preliminary version of the process map and first estimation of research-related contributions. In the second stage, potential key-users and other informants are interviewed to trace, explore and triangulate possible contributions. In the third stage, the presence and role of alignment efforts is analyzed and the preliminary results are shared with relevant stakeholders for feedback and validation. After inconsistencies are clarified or described, the results are shared with stakeholders for learning, improvement and accountability purposes.Conclusion: Contribution Mapping provides an interesting alternative to existing methods that aim to assess research impact. The method is expected to be useful for research monitoring, single case studies, comparing multiple cases and indicating how research can better be employed to contribute to better action for health. © 2012 Kok and Schuit; licensee BioMed Central Ltd

    Law after Lehmans

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    The September 2008 collapse of the Lehman Brothers group marked the nadir of the global financial crisis. While the regulatory aftermath has been extensively debated, the effects of the case law that arose from the insolvency have not. This paper explains the need to redress the balance. It starts by considering the quantity and qualities of the Lehmans case law, examining why the 30 plus decisions handed down by the English courts enjoy an unusually high precedent-setting potential. The paper proceeds by analysing the precedential effects of these decisions, and it reports on a recent workshop held at the London School of Economics that met to consider this question. Subject to the event’s terms of engagement, the paper draws out several themes from the discussion, including the impact of the Lehmans cases on the principles of contractual interpretation, the law of trusts and insolvency law. By way of conclusion, it is submitted that the impact of Lehmans case law reaches far beyond that particular insolvency, to worldwide users of standard form documents, the global financial markets and the common law itself. Seen in this light, the Lehmans case law is a significant, but under-appreciated, side-effect of the global financial crisis
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