68 research outputs found
Molecular basis for maize as a risk factor for oesophageal cancer in a South African population
Throughout the world squamous cell carcinoma of the oesophagus seems to be an increasing problem. There is a huge variation in prevalence globally; locations such as Japan, Iran, China and Finland can have ten times the prevalence compared to other western countries. One place that is hugely affected is Transkei, a 16,000 square mile area of South Africa. Some of the factors proposed to be implicated with squamous cell carcinoma in this region include tobacco smoking, alcohol consumption, bacterial infections and fungal infection of common food crops. In addition, the ‘Sammon theory’ links carcinogenesis in Transkei to the high consumption of maize by the population. Through a chain of reactions it is postulated that a component of maize inhibits the breakdown of growth factors, which have already been implicated in cancer. This study investigates the Transkei population and updates the Sammon theory with current research to predict a theory at a molecular level. This theory is then tested with novel research to show PGE2, shown here in high concentrations in gastric fluid samples, directly increases the proliferation of oesophageal cell lines. Gastric fluid samples from the Transkei population are then shown to have a mitogenic effect on oesophageal cells, supporting a theory that gastric fluid regurgitation commonly found in this population predisposes them to cancer. Further experimentation on the expression of related proteins shows how high PGE2 may increase its own production by increasing COX 2 expression, leading to a positive feedback loop causing constant proliferative stimulation of the oesophageal squamous tissue in the presence of the COX 2 substrate, aracadonic acid. Therefore this thesis suggests that a high maize diet provides the correct conditions for regurgitation of increased concentrations of PGE2 into the oesophagus leading to squamous hyper-proliferation over long periods of time through self stimulated production, which would normally have ceased over a much shorter time if only localised PGE2 was produced through natural restitution.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
In sickness and in health : The functional role of extracellular vesicles in physiology and pathology in vivo Part II: Pathology
It is clear from Part I of this series that extracellular vesicles (EVs) play a critical role in maintaining the homeostasis of most, if not all, normal physiological systems. However, the majority of our knowledge about EV signalling has come from studying them in disease. Indeed, EVs have consistently been associated with propagating disease pathophysiology. The analysis of EVs in biofluids, obtained in the clinic, has been an essential of the work to improve our understanding of their role in disease. However, to interfere with EV signalling for therapeutic gain, a more fundamental understanding of the mechanisms by which they contribute to pathogenic processes is required. Only by discovering how the EV populations in different biofluids change-size, number, and physicochemical composition-in clinical samples, may we then begin to unravel their functional roles in translational models in vitro and in vivo, which can then feedback to the clinic. In Part II of this review series, the functional role of EVs in pathology and disease will be discussed, with a focus on in vivo evidence and their potential to be used as both biomarkers and points of therapeutic intervention.Peer reviewe
In sickness and in health : The functional role of extracellular vesicles in physiology and pathology in vivo Part II: Pathology
It is clear from Part I of this series that extracellular vesicles (EVs) play a critical role in maintaining the homeostasis of most, if not all, normal physiological systems. However, the majority of our knowledge about EV signalling has come from studying them in disease. Indeed, EVs have consistently been associated with propagating disease pathophysiology. The analysis of EVs in biofluids, obtained in the clinic, has been an essential of the work to improve our understanding of their role in disease. However, to interfere with EV signalling for therapeutic gain, a more fundamental understanding of the mechanisms by which they contribute to pathogenic processes is required. Only by discovering how the EV populations in different biofluids change-size, number, and physicochemical composition-in clinical samples, may we then begin to unravel their functional roles in translational models in vitro and in vivo, which can then feedback to the clinic. In Part II of this review series, the functional role of EVs in pathology and disease will be discussed, with a focus on in vivo evidence and their potential to be used as both biomarkers and points of therapeutic intervention.Peer reviewe
In sickness and in health : The functional role of extracellular vesicles in physiology and pathology in vivo Part I: Health and Normal Physiology
Previously thought to be nothing more than cellular debris, extracellular vesicles (EVs) are now known to mediate physiological and pathological functions throughout the body. We now understand more about their capacity to transfer nucleic acids and proteins between distant organs, the interaction of their surface proteins with target cells, and the role of vesicle-bound lipids in health and disease. To date, most observations have been made in reductionist cell culture systems, or as snapshots from patient cohorts. The heterogenous population of vesicles produced in vivo likely act in concert to mediate both beneficial and detrimental effects. EVs play crucial roles in both the pathogenesis of diseases, from cancer to neurodegenerative disease, as well as in the maintenance of system and organ homeostasis. This two-part review draws on the expertise of researchers working in the field of EV biology and aims to cover the functional role of EVs in physiology and pathology. Part I will outline the role of EVs in normal physiology.Peer reviewe
Photo-elicitation: using photographs to read retail interiors through consumers' eyes
Researchers studying experiences in retail environments have typically restricted their attention towards examining the influence of individual atmospheric variables upon customer behavior. In this respect photographs and video are common environmental simulation techniques. This research approach not only concerns researchers active in consumer culture theory, but also interior architects and retail designers. As holistic inspired practitioners, they maintain that interiors function as 'Gestalt' environments, interacting with their users. Inspired by their viewpoints, in this paper, the authors reflect on the use of the inductive, holistically inspired method of photo-elicitation in research concerning experiences in retail environments. In addition, they report on the application of photo-elicitation in two empirical projects. The findings demonstrate the value of photo-elicitation in gaining insight into customer experiences in retail interiors
SARS Coronavirus-2 microneutralisation and commercial serological assays correlated closely for some but not all enzyme immunoassays
Serological testing for SARS-CoV-2-specific antibodies provides important research and diagnostic information relating to COVID-19 prevalence, incidence and host immune response. A greater understanding of the relationship between functionally neutralising antibodies detected using microneutralisation assays and binding antibodies detected using scalable enzyme immunoassays (EIA) is needed in order to address protective immunity post-infection or vaccination, and assess EIA suitability as a surrogate test for screening of convalescent plasma donors. We assessed whether neutralising antibody titres correlated with signal cut-off ratios in five commercially available EIAs, and one in-house assay based on expressed spike protein targets. Sera from recovered patients or convalescent plasma donors who reported laboratory-confirmed SARS-CoV-2 infection (n = 200), and negative control sera collected prior to the COVID-19 pandemic (n = 100), were assessed in parallel. Performance was assessed by calculating EIA sensitivity and specificity with reference to microneutralisation. Neutralising antibodies were detected in 166 (83%) samples. Compared with this, the most sensitive EIAs were the Cobas Elecsys Anti-SARS-CoV-2 (98%) and Vitros Immunodiagnostic Anti-SARS-CoV-2 (100%), which detect total antibody targeting the N and S1 antigens, respectively. The assay with the best quantitative relationship with microneutralisation was the Euroimmun IgG. These results suggest the marker used (total Ab vs. IgG vs. IgA) and the target antigen are important determinants of assay performance. The strong correlation between microneutralisation and some commercially available assays demonstrates their potential for clinical and research use in assessing protection following infection or vaccination, and use as a surrogate test to assess donor suitability for convalescent plasma donation
In sickness and in health: The functional role of extracellular vesicles in physiology and pathology in vivo. Part 2
It is clear from Part I of this series that extracellular vesicles (EVs) play a critical role in maintaining the homeostasis of most, if not all, normal physiological systems. However, the majority of our knowledge about EV signalling has come from studying them in disease. Indeed, EVs have consistently been associated with propagating disease pathophysiology. The analysis of EVs in biofluids, obtained in the clinic, has been an essential of the work to improve our understanding of their role in disease. However, to interfere with EV signalling for therapeutic gain, a more fundamental understanding of the mechanisms by which they contribute to pathogenic processes is required. Only by discovering how the EV populations in different biofluids change—size, number, and physicochemical composition—in clinical samples, may we then begin to unravel their functional roles in translational models in vitro and in vivo, which can then feedback to the clinic. In Part II of this review series, the functional role of EVs in pathology and disease will be discussed, with a focus on in vivo evidence and their potential to be used as both biomarkers and points of therapeutic intervention
Rehabilitation of memory following brain injury (ReMemBrIn): study protocol for a randomised controlled trial
Background
Impairments of memory are commonly reported by people with traumatic brain injuries (TBI). Such deficits are persistent, debilitating, and can severely impact quality of life. Currently, many do not routinely receive follow-up appointments for residual memory problems following discharge.
Methods/Design
This is a multi-centre, randomised controlled trial investigating the clinical and cost-effectiveness of a group-based memory rehabilitation programme. Three hundred and twelve people with a traumatic brain injury will be randomised from four centres. Participants will be eligible if they had a traumatic brain injury more than 3 months prior to recruitment, have memory problems, are 18 to 69 years of age, are able to travel to one of our centres and attend group sessions, and are able to give informed consent. Participants will be randomised in clusters of 4 to 6 to the group rehabilitation intervention or to usual care. Intervention groups will receive 10 weekly sessions of a manualised memory rehabilitation programme, which has been developed in previous pilot studies. The intervention will include restitution strategies to retrain impaired memory functions and compensation strategies to enable participants to cope with their memory problems. All participants will receive a follow-up postal questionnaire and an assessment by a research assistant at 6 and 12 months post-randomisation. The primary outcome is the Everyday Memory Questionnaire at 6 months. Secondary outcomes include the Rivermead Behavioural Memory Test-3, General Health Questionnaire-30, health related quality of life, cost-effectiveness analysis determined by the EQ-5D and a service use questionnaire, individual goal attainment, European Brain Injury Questionnaire (patient and relative versions), and the Everyday Memory Questionnaire-relative version. The primary analysis will be based on intention to treat. A mixed-model regression analysis of the Everyday Memory Questionnaire at 6 months will be used to estimate the effect of the group memory rehabilitation programme.
Discussion
The study will hopefully provide robust evidence regarding the clinical and cost-effectiveness of a group-based memory rehabilitation intervention for civilians and military personnel following TBI. We discuss our decision-making regarding choice of outcome measures and control group, and the unique challenges to recruiting people with memory problems to trials
Walking with Media: Towards a mixed reality pedagogy in university learning environments
Recently the fields of architecture, media studies, and education have begun to converge through the proliferation of mixed reality technologies and interfaces. This convergence is widely described as offering new opportunities for immersive, seamless, decentralised and environmentally distributed learning experiences. This chapter contributes to a growing body of research exploring the transformation of learning environments through distributed media networks, digital databases, and innovative pedagogical interventions. It develops a theoretical framework for researching the interconnections between the built environment, mixed reality technologies, and place-based learning experiences and pedagogies. The second part of the chapter focuses on the development of the CubeWalk network, which involved a series of site-specific architectural installations, digital interfaces, and pedagogical interventions on a university campus in NSW, Australia. Two case studies are presented which describe the co-design and evaluation of mixed reality tutorial walks across the university campus. Drawing together insights rendered through the case studies, the chapter offers a series of theoretical propositions for a ‘mixed reality pedagogy’ that is distributed across 21st century learning environments and media networks
Understanding adaptation to first episode psychosis through the creation of images
This article aims to understand and explore the meaning of adaptation to First Episode Psychosis (FEP). An innovative method of data collection was used with ten participants who experienced FEP which integrated drawings of their lived experience within semi-structured interviews. The data were analysed through Interpretative Phenomenological Analysis and hermeneutic-phenomenological image analysis. Participants’ experience was captured in four superordinate themes which identified that adaptation to FEP entailed: ‘Finding out how psychosis fits into my story’, ‘Breaking free from psychosis’, ‘Fighting my way through psychosis’, and ‘Finding a new way of being ‘me’’. The participants’ path of adaptation to FEP was an interplay of pains, challenges, and gains, and there was resonance with posttraumatic growth in their accounts. This article illustrates that creating images may offer a powerful way of conveying the multifaceted aspects of adaptation to FEP and could help individuals in communicating and processing their experience
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