101 research outputs found
Neutrophils in cancer: neutral no more
Neutrophils are indispensable antagonists of microbial infection and facilitators of wound healing. In the cancer setting, a newfound appreciation for neutrophils has come into view. The traditionally held belief that neutrophils are inert bystanders is being challenged by the recent literature. Emerging evidence indicates that tumours manipulate neutrophils, sometimes early in their differentiation process, to create diverse phenotypic and functional polarization states able to alter tumour behaviour. In this Review, we discuss the involvement of neutrophils in cancer initiation and progression, and their potential as clinical biomarkers and therapeutic targets
Effectiveness and cost-effectiveness of a telehealth intervention to support the management of long-term conditions: study protocol for two linked randomized controlled trials
Background: As the population ages, more people are suffering from long-term health conditions (LTCs). Health
services around the world are exploring new ways of supporting people with LTCs and there is great interest in the
use of telehealth: technologies such as the Internet, telephone and home self-monitoring.
Methods/Design: This study aims to evaluate the effectiveness and cost-effectiveness of a telehealth intervention
delivered by NHS Direct to support patients with LTCs. Two randomized controlled trials will be conducted in parallel,
recruiting patients with two exemplar LTCs: depression or raised cardiovascular disease (CVD) risk. A total of 1,200
patients will be recruited from approximately 42 general practices near Bristol, Sheffield and Southampton, UK.
Participants will be randomly allocated to either usual care (control group) or usual care plus the NHS Direct
Healthlines Service (intervention group). The intervention is based on a conceptual model incorporating promotion of
self-management, optimisation of treatment, coordination of care and engagement of patients and general
practitioners. Participants will be provided with tailored help, combining telephone advice from health information
advisors with support to use a range of online resources. Participants will access the service for 12 months. Outcomes
will be collected at baseline, four, eight and 12 months for the depression trial and baseline, six and 12 months for
the CVD risk trial. The primary outcome will be the proportion of patients responding to treatment, defined in the
depression trial as a PHQ-9 score <10 and an absolute reduction in PHQ-9 ≥5 after 4 months, and in the CVD risk
trial as maintenance or reduction of 10-year CVD risk after 12 months. The study will also assess whether the
intervention is cost-effective from the perspective of the NHS and personal social services. An embedded qualitative
interview study will explore healthcare professionals’ and patients’ views of the intervention.
Discussion: This study evaluates a complex telehealth intervention which combines evidence-based components and
is delivered by an established healthcare organisation. The study will also analyse health economic information. In
doing so, the study hopes to address some of the limitations of previous research by demonstrating the effectiveness
and cost-effectiveness of a real world telehealth interventio
Using high angular resolution diffusion imaging data to discriminate cortical regions
Brodmann's 100-year-old summary map has been widely used for cortical localization in neuroscience. There is a pressing need to update this map using non-invasive, high-resolution and reproducible data, in a way that captures individual variability. We demonstrate here that standard HARDI data has sufficiently diverse directional variation among grey matter regions to inform parcellation into distinct functional regions, and that this variation is reproducible across scans. This characterization of the signal variation as non-random and reproducible is the critical condition for successful cortical parcellation using HARDI data. This paper is a first step towards an individual cortex-wide map of grey matter microstructure, The gray/white matter and pial boundaries were identified on the high-resolution structural MRI images. Two HARDI data sets were collected from each individual and aligned with the corresponding structural image. At each vertex point on the surface tessellation, the diffusion-weighted signal was extracted from each image in the HARDI data set at a point, half way between gray/white matter and pial boundaries. We then derived several features of the HARDI profile with respect to the local cortical normal direction, as well as several fully orientationally invariant features. These features were taken as a fingerprint of the underlying grey matter tissue, and used to distinguish separate cortical areas. A support-vector machine classifier, trained on three distinct areas in repeat 1 achieved 80-82% correct classification of the same three areas in the unseen data from repeat 2 in three volunteers. Though gray matter anisotropy has been mostly overlooked hitherto, this approach may eventually form the foundation of a new cortical parcellation method in living humans. Our approach allows for further studies on the consistency of HARDI based parcellation across subjects and comparison with independent microstructural measures such as ex-vivo histology
Adaptive Robotic Control Driven by a Versatile Spiking Cerebellar Network
The cerebellum is involved in a large number of different neural processes, especially in associative learning and in fine motor control. To develop a comprehensive theory of sensorimotor learning and control, it is crucial to determine the neural basis of coding and plasticity embedded into the cerebellar neural circuit and how they are translated into behavioral outcomes in learning paradigms. Learning has to be inferred from the interaction of an embodied system with its real environment, and the same cerebellar principles derived from cell physiology have to be able to drive a variety of tasks of different nature, calling for complex timing and movement patterns. We have coupled a realistic cerebellar spiking neural network (SNN) with a real robot and challenged it in multiple diverse sensorimotor tasks. Encoding and decoding strategies based on neuronal firing rates were applied. Adaptive motor control protocols with acquisition and extinction phases have been designed and tested, including an associative Pavlovian task (Eye blinking classical conditioning), a vestibulo-ocular task and a perturbed arm reaching task operating in closed-loop. The SNN processed in real-time mossy fiber inputs as arbitrary contextual signals, irrespective of whether they conveyed a tone, a vestibular stimulus or the position of a limb. A bidirectional long-term plasticity rule implemented at parallel fibers-Purkinje cell synapses modulated the output activity in the deep cerebellar nuclei. In all tasks, the neurorobot learned to adjust timing and gain of the motor responses by tuning its output discharge. It succeeded in reproducing how human biological systems acquire, extinguish and express knowledge of a noisy and changing world. By varying stimuli and perturbations patterns, real-time control robustness and generalizability were validated. The implicit spiking dynamics of the cerebellar model fulfill timing, prediction and learning functions.European Union (Human Brain Project)
REALNET FP7-ICT270434
CEREBNET FP7-ITN238686
HBP-60410
Patterns of neonatal hypoxic–ischaemic brain injury
Enormous progress has been made in assessing the neonatal brain, using magnetic resonance imaging (MRI). In this review, we will describe the use of MRI and proton magnetic resonance spectroscopy in detecting different patterns of brain injury in (full-term) human neonates following hypoxic–ischaemic brain injury and indicate the relevance of these findings in predicting neurodevelopmental outcome
Strategies for improving patient recruitment to focus groups in primary care: a case study reflective paper using an analytical framework
<p>Abstract</p> <p>Background</p> <p>Recruiting to primary care studies is complex. With the current drive to increase numbers of patients involved in primary care studies, we need to know more about successful recruitment approaches. There is limited evidence on recruitment to focus group studies, particularly when no natural grouping exists and where participants do not regularly meet. The aim of this paper is to reflect on recruitment to a focus group study comparing the methods used with existing evidence using a resource for research recruitment, PROSPeR (Planning Recruitment Options: Strategies for Primary Care).</p> <p>Methods</p> <p>The focus group formed part of modelling a complex intervention in primary care in the Resources for Effective Sleep Treatment (REST) study. Despite a considered approach at the design stage, there were a number of difficulties with recruitment. The recruitment strategy and subsequent revisions are detailed.</p> <p>Results</p> <p>The researchers' modifications to recruitment, justifications and evidence from the literature in support of them are presented. Contrary evidence is used to analyse why some aspects were unsuccessful and evidence is used to suggest improvements. Recruitment to focus group studies should be considered in two distinct phases; getting potential participants to contact the researcher, and converting those contacts into attendance. The difficulty of recruitment in primary care is underemphasised in the literature especially where people do not regularly come together, typified by this case study of patients with sleep problems.</p> <p>Conclusion</p> <p>We recommend training GPs and nurses to recruit patients during consultations. Multiple recruitment methods should be employed from the outset and the need to build topic related non-financial incentives into the group meeting should be considered. Recruitment should be monitored regularly with barriers addressed iteratively as a study progresses.</p
Mixed Th1 and Th2 Mycobacterium tuberculosis-specific CD4 T cell responses in patients with active pulmonary tuberculosis from Tanzania.
Mycobacterium tuberculosis (Mtb) and helminth infections elicit antagonistic immune effector functions and are co-endemic in several regions of the world. We therefore hypothesized that helminth infection may influence Mtb-specific T-cell immune responses. We evaluated the cytokine profile of Mtb-specific T cells in 72 individuals with pulmonary TB disease recruited from two Sub-Saharan regions with high and moderate helminth burden i.e. 55 from Tanzania (TZ) and 17 from South Africa (SA), respectively. We showed that Mtb-specific CD4 T-cell functional profile of TB patients from Tanzania are primarily composed of polyfunctional Th1 and Th2 cells, associated with increased expression of Gata-3 and reduced expression of T-bet in memory CD4 T cells. In contrast, the cytokine profile of Mtb-specific CD4 T cells of TB patients from SA was dominated by single IFN-γ and dual IFN-γ/TNF-α and associated with TB-induced systemic inflammation and elevated serum levels of type I IFNs. Of note, the proportion of patients with Mtb-specific CD8 T cells was significantly reduced in Mtb/helminth co-infected patients from TZ. It is likely that the underlying helminth infection and possibly genetic and other unknown environmental factors may have caused the induction of mixed Th1/Th2 Mtb-specific CD4 T cell responses in patients from TZ. Taken together, these results indicate that the generation of Mtb-specific CD4 and CD8 T cell responses may be substantially influenced by environmental factors in vivo. These observations may have major impact in the identification of immune biomarkers of disease status and correlates of protection
Controlled Trial of Transfusions for Silent Cerebral Infarcts in Sickle Cell Anemia
BACKGROUND
Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular bloodtransfusion therapy than among those who received standard care.
METHODS
In this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or
standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic
resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct.
RESULTS
A total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and
observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P=0.04).
CONCLUSIONS
Regular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National
Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and
Current Controlled Trials number, ISRCTN52713285.
Exploring service providers’ perspectives on the prevention and management of fetal alcohol spectrum disorders in South Africa: a qualitative study
BACKGROUND: Fetal alcohol spectrum disorder (FASD) is among the leading causes of developmental and intellectual
disabilities in individuals. Although efforts are being made toward the prevention and management of FASD in South
Africa, the prevalence remains high. The sustained high prevalence could be attributed to several factors, including the
lack of policy for a coordinated effort to prevent, diagnose and manage FASD nationally. In this study, our aim was to
explore the perspectives of service providers (health and allied professionals, teachers, social workers) on the
prevention and management of FASD towards developing a guideline to inform policy.
METHOD: Guided by the exploratory qualitative research design, we purposively sampled relevant service
providers in the field of FASD prevention and management for focus group discussions. Nine of these
discussions were conducted with to eight participants per discussion session. The discussants were asked various
questions on the current and required interventions and practices for the prevention and management of FASD.
Following the Framework Method, data were transcribed verbatim and analysed using the thematic content analysis
approach.
RESULTS: Our findings show that aspects of the prevention and management of alcohol-related conditions are present
in various policies. However, there is no clear focus on coordinated, multi-sectoral efforts for a more comprehensive
approach to the prevention and management of FASD. The participants recognized the need for specific requirements
on broad-based preventive awareness programs, training and support for parents and caregivers, inclusive education in
mainstream schools and training of relevant professionals.
CONCLUSION: Comprehensive and coordinated prevention and management programs guided by a specific policy
could improve the prevention and management of FASD. Policy formulation demonstrates commitment from the
government, highlights the importance of the condition, and elaborates on context-specific prevention and management
protocols.IS
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