19 research outputs found
2-Deoxy-D-glucose enhances TRAIL-induced apoptosis in human melanoma cells through XBP-1-mediated up-regulation of TRAIL-R2
Background: Past studies have shown that sensitivity of melanoma cells to TRAIL-induced apoptosis is largely correlated with the expression levels of TRAIL death receptors on the cell surface. However, fresh melanoma isolates and melanoma tissue sections express generally low levels of death receptors for TRAIL. The clinical potential of TRAIL in the treatment of melanoma may therefore be limited unless given with agents that increase the cell surface expression of TRAIL death receptors. 2-Deoxy-D-glucose (2-DG) is a synthetic glucose analogue that inhibits glycolysis and glycosylation and blocks cell growth. It has been in clinical evaluation for its potential use as an anticancer agent. In this study, we have examined whether 2-DG and TRAIL interact to enhance their cytotoxicity towards melanoma cells. Results: 2-DG did not kill melanoma cells, but enhanced TRAIL-induced apoptosis in cultured melanoma cells and fresh melanoma isolates. This was associated with increased activation of the caspase cascade and mitochondrial apoptotic pathway, and was blocked by inhibition of TRAIL-R2, and to a lesser extent, inhibition of TRAIL-R1. Treatment with 2-DG up-regulated TRAIL death receptors, in particular, TRAIL-R2, on the melanoma cell surface. Up-regulation of TRAIL-R2 was due to increased transcription that was not dependent on the transcription factors, p53 and CHOP. Instead, the IRE1α and ATF6 pathways of the unfolded protein response that were activated by 2-DG appeared to be involved. Moreover, XBP-1, which is known to be transcriptionally regulated by ATF6 and functionally activated by IRE1α, was found to play an important role in 2-DG-mediated transcriptional up-regulation of TRAIL-R2 in melanoma cells. Conclusion: These results indicate that 2-DG sensitizes human melanoma cells to TRAIL-induced apoptosis by up-regulation of TRAIL-2 via the ATF6/IRE1α/XBP-1 axis of the unfolded protein response. They suggest that 2-DG is a promising agent to increase the therapeutic response to TRAIL in melanoma
Nature and reporting characteristics of UK health technology assessment systematic reviews
BACKGROUND: A recent study by Page et al. (PLoS Med. 2016;13(5):e1002028) claimed that increasing numbers of reviews are being published and many are poorly-conducted and reported. The aim of the present study was to assess how well reporting standards of systematic reviews produced in a Health Technology Assessment (HTA) context compare with reporting in Cochrane and other 'non-Cochrane' systematic reviews from the same years (2004 and 2014), as reported by Page et al. (PLoS Med. 2016;13(5):e1002028). METHODS: All relevant UK HTA programme systematic reviews published in 2004 and 2014 were identified. After piloting of the form, two reviewers each extracted relevant data on conduct and reporting from these reviews. These data were compared with data for Cochrane and "non-Cochrane" systematic reviews, as published by Page et al. (PLoS Med. 2016;13(5):e1002028). All data were tabulated and summarized. RESULTS: There were 30 UK HTA programme systematic reviews and 300 other systematic reviews, including Cochrane reviews (n = 45). The percentage of HTA reviews with required elements of conduct and reporting was frequently very similar to Cochrane and much higher than all other systematic reviews, e.g. availability of protocols (90, 98 and 16% respectively); the specification of study design criteria (100, 100, 79%); the reporting of outcomes (100, 100, 78%), quality assessment (100, 100, 70%); the searching of trial registries for unpublished data (70, 62, 19%); reporting of reasons for excluding studies (91, 91 and 70%) and reporting of authors' conflicts of interests (100, 100, 87%). HTA reviews only compared less favourably with Cochrane and other reviews in assessments of publication bias. CONCLUSIONS: UK HTA systematic reviews are often produced within a specific policy-making context. This context has implications for timelines, tools and resources. However, UK HTA systematic reviews still tend to present standards of conduct and reporting equivalent to "gold standard" Cochrane reviews and superior to systematic reviews more generally
Implementing health research through academic and clinical partnerships : a realistic evaluation of the Collaborations for Leadership in Applied Health Research and Care (CLAHRC)
Background: The English National Health Service has made a major investment in nine partnerships between
higher education institutions and local health services called Collaborations for Leadership in Applied Health
Research and Care (CLAHRC). They have been funded to increase capacity and capability to produce and
implement research through sustained interactions between academics and health services. CLAHRCs provide a
natural ‘test bed’ for exploring questions about research implementation within a partnership model of delivery.
This protocol describes an externally funded evaluation that focuses on implementation mechanisms and
processes within three CLAHRCs. It seeks to uncover what works, for whom, how, and in what circumstances.
Design and methods: This study is a longitudinal three-phase, multi-method realistic evaluation, which
deliberately aims to explore the boundaries around knowledge use in context. The evaluation funder wishes to see
it conducted for the process of learning, not for judging performance. The study is underpinned by a conceptual
framework that combines the Promoting Action on Research Implementation in Health Services and Knowledge to
Action frameworks to reflect the complexities of implementation. Three participating CLARHCS will provide indepth
comparative case studies of research implementation using multiple data collection methods including
interviews, observation, documents, and publicly available data to test and refine hypotheses over four rounds of
data collection. We will test the wider applicability of emerging findings with a wider community using an
interpretative forum.
Discussion: The idea that collaboration between academics and services might lead to more applicable health
research that is actually used in practice is theoretically and intuitively appealing; however the evidence for it is
limited. Our evaluation is designed to capture the processes and impacts of collaborative approaches for
implementing research, and therefore should contribute to the evidence base about an increasingly popular (e.g.,
Mode two, integrated knowledge transfer, interactive research), but poorly understood approach to knowledge
translation. Additionally we hope to develop approaches for evaluating implementation processes and impacts
particularly with respect to integrated stakeholder involvement
Multicolour Single Molecule Imaging in Cells with Near Infra-Red Dyes
Background: The autofluorescence background of biological samples impedes the detection of single molecules when imaging. The most common method of reducing the background is to use evanescent field excitation, which is incompatible with imaging beyond the surface of biological samples. An alternative would be to use probes that can be excited in the near infra-red region of the spectrum, where autofluorescence is low. Such probes could also increase the number of labels that can be imaged in multicolour single molecule microscopes. Despite being widely used in ensemble imaging, there is a currently a shortage of information available for selecting appropriate commercial near infra-red dyes for single molecule work. It is therefore important to characterise available near infra-red dyes relevant to multicolour single molecule imaging. Methodology/Principal Findings: A range of commercially available near infra-red dyes compatible with multi-colour imaging was screened to find the brightest and most photostable candidates. Image series of immobilised samples of the brightest dyes (Alexa 700, IRDye 700DX, Alexa 790 and IRDye 800CW) were analysed to obtain the mean intensity of single dye molecules, their photobleaching rates and long period blinking kinetics. Using the optimum dye pair, we have demonstrated for the first time widefield, multi-colour, near infra-red single molecule imaging using a supercontinuum light source in MCF-7 cells
Thirty years after Alma-Ata: a systematic review of the impact of community health workers delivering curative interventions against malaria, pneumonia and diarrhoea on child mortality and morbidity in sub-Saharan Africa
BACKGROUND: Over thirty years have passed since the Alma-Ata Declaration on primary health care in 1978. Many governments in the first decade following the declaration responded by developing national programmes of community health workers (CHWs), but evaluations of these often demonstrated poor outcomes. As many CHW programmes have responded to the HIV/AIDS pandemic, international interest in them has returned and their role in the response to other diseases should be examined carefully so that lessons can be applied to their new roles. Over half of the deaths in African children under five years of age are due to malaria, diarrhoea and pneumonia - a situation which could be addressed through the use of cheap and effective interventions delivered by CHWs. However, to date there is very little evidence from randomised controlled trials of the impacts of CHW programmes on child mortality in Africa. Evidence from non-randomised controlled studies has not previously been reviewed systematically. METHODS: We searched databases of published and unpublished studies for RCTs and non-randomised studies evaluating CHW programmes delivering curative treatments, with or without preventive components, for malaria, diarrhoea or pneumonia, in children in sub-Saharan Africa from 1987 to 2007. The impact of these programmes on morbidity or mortality in children under six years of age was reviewed. A descriptive analysis of interventional and contextual factors associated with these impacts was attempted. RESULTS: The review identified seven studies evaluating CHWs, delivering a range of interventions. Limited descriptive data on programmes, contexts or process outcomes for these CHW programmes were available. CHWs in national programmes achieved large mortality reductions of 63% and 36% respectively, when insecticide-treated nets and anti-malarial chemoprophylaxis were delivered, in addition to curative interventions. CONCLUSIONS: CHW programmes could potentially achieve large gains in child survival in sub-Saharan Africa if these programmes were implemented at scale. Large-scale rigorous studies, including RCTs, are urgently needed to provide policymakers with more evidence on the effects of CHWs delivering these interventions
Role and use of evidence in policymaking: an analysis of case studies from the health sector in Nigeria.
Background Health policymaking is a complex process and analysing the role of evidence is still an evolving area in many low- and middle-income countries. Where evidence is used, it is greatly affected by cognitive and institutional features of the policy process. This paper examines the role of different types of evidence in health policy development in Nigeria. Methods The role of evidence was compared between three case studies representing different health policies, namely the (1) integrated maternal neonatal and child health strategy (IMNCH); (2) oral health (OH) policy; and (3) human resource for health (HRH) policy. The data was collected using document reviews and 31 in-depth interviews with key policy actors. Framework Approach was used to analyse the data, aided by NVivo 10 software. Results Most respondents perceived evidence to be factual and concrete to support a decision. Evidence was used more if it was perceived to be context-specific, accessible and timely. Low-cost high-impact evidence, such as the Lancet series, was reported to have been used in drafting the IMNCH policy. In the OH and HRH policies, informal evidence such as experts’ experiences and opinions, were reported to have been useful in the policy drafting stage. Both formal and informal evidence were mentioned in the HRH and OH policies, while the development of the IMNCH was revealed to have been informed mainly by more formal evidence. Overall, respondents suggested that formal evidence, such as survey reports and research publications, were most useful in the agenda-setting stage to identify the need for the policy and thus initiating the policy development process. International and local evidence were used to establish the need for a policy and develop policy, and less to develop policy implementation options. Conclusion Recognition of the value of different evidence types, combined with structures for generating and using evidence, are likely to enhance evidence-informed health policy development in Nigeria and other similar contexts
Rat testicular myoid cells express vasopressin receptors:Receptor structure, signal transduction, and developmental regulation
Understanding the performance and impact of public knowledge translation funding interventions: Protocol for an evaluation of Canadian Institutes of Health Research knowledge translation funding programs
The Implementation in Context (ICON) Framework: A meta-framework of context domains, attributes and features in healthcare
Background There is growing evidence that context mediates the effects of implementation interventions intended to increase healthcare professionals’ use of research evidence in clinical practice. However, conceptual clarity about what comprises context is elusive. The purpose of this study was to advance conceptual clarity on context by developing the Implementation in Context Framework, a meta-framework of the context domains, attributes and features that can facilitate or hinder healthcare professionals’ use of research evidence and the effectiveness of implementation interventions in clinical practice. Methods We conducted a meta-synthesis of data from three interrelated studies: (1) a concept analysis of published literature on context (n = 70 studies), (2) a secondary analysis of healthcare professional interviews (n = 145) examining context across 11 unique studies and (3) a descriptive qualitative study comprised of interviews with heath system stakeholders (n = 39) in four countries to elicit their tacit knowledge on the attributes and features of context. A rigorous protocol was followed for the meta-synthesis, resulting in development of the Implementation in Context Framework. Following this meta-synthesis, the framework was further refined through feedback from experts in context and implementation science. Results In the Implementation in Context Framework, context is conceptualized in three levels: micro (individual), meso (organizational), and macro (external). The three levels are composed of six contextual domains: (1) actors (micro), (2) organizational climate and structures (meso), (3) organizational social behaviour (meso), (4) organizational response to change (meso), (5) organizational processes (meso) and (6) external influences (macro). These six domains contain 22 core attributes of context and 108 features that illustrate these attributes. Conclusions The Implementation in Context Framework is the only meta-framework of context available to guide implementation efforts of healthcare professionals. It provides a comprehensive and critically needed understanding of the context domains, attributes and features relevant to healthcare professionals’ use of research evidence in clinical practice. The Implementation in Context Framework can inform implementation intervention design and delivery to better interpret the effects of implementation interventions, and pragmatically guide implementation efforts that enhance evidence uptake and sustainability by healthcare professionals