1,033 research outputs found
PREDICT-PD: Identifying risk of Parkinson's disease in the community: methods and baseline results
To present methods and baseline results for an online screening tool to identify increased risk for Parkinson's disease (PD) in the UK population
P2Y Receptors Sensitize Mouse and Human Colonic Nociceptors
Activation of visceral nociceptors by inflammatory mediators contributes to visceral hypersensitivity and abdominal pain associated with many gastrointestinal disorders. Purine and pyrimidine nucleotides (e.g., ATP and UTP) are strongly implicated in this process following their release from epithelial cells during mechanical stimulation of the gut, and from immune cells during inflammation. Actions of ATP are mediated through both ionotropic P2X receptors and metabotropic P2Y receptors. P2X receptor activation causes excitation of visceral afferents; however, the impact of P2Y receptor activation on visceral afferents innervating the gut is unclear. Here we investigate the effects of stimulating P2Y receptors in isolated mouse colonic sensory neurons, and visceral nociceptor fibers in mouse and human nerve-gut preparations. Additionally, we investigate the role of Na(v)1.9 in mediating murine responses. The application of UTP (P2Y(2) and P2Y(4) agonist) sensitized colonic sensory neurons by increasing action potential firing to current injection and depolarizing the membrane potential. The application of ADP (P2Y(1), P2Y(12), and P2Y(13) agonist) also increased action potential firing, an effect blocked by the selective P2Y(1) receptor antagonist MRS2500. UTP or ADP stimulated afferents, including mouse and human visceral nociceptors, in nerve-gut preparations. P2Y(1) and P2Y(2) transcripts were detected in 80% and 56% of retrogradely labeled colonic neurons, respectively. Na(v)1.9 transcripts colocalized in 86% of P2Y(1)-positive and 100% of P2Y(2)-positive colonic neurons, consistent with reduced afferent fiber responses to UTP and ADP in Na(v)1.9(−/−) mice. These data demonstrate that P2Y receptor activation stimulates mouse and human visceral nociceptors, highlighting P2Y-dependent mechanisms in the generation of visceral pain during gastrointestinal disease. SIGNIFICANCE STATEMENT Chronic visceral pain is a debilitating symptom of many gastrointestinal disorders. The activation of pain-sensing nerves located in the bowel wall and their sensitization to physiological stimuli, including bowel movements, underpins the development of such pain, and is associated with mediators released during disease. This work addresses the unstudied role of purine and pyrimidine nucleotides in modulating colonic nociceptors via P2Y receptors using a combination of electrophysiological recordings from human ex vivo samples and a detailed functional study in the mouse. This is the first report to identify colonic purinergic signaling as a function of P2Y receptor activation, in addition to established P2X receptor activity, and the results contribute to our understanding of the development of visceral pain during gastrointestinal disease
Interpreting ambiguous ‘trace’ results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard
Background The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous ‘trace’ result between ‘positive’ and ‘negative’, and much debate has focused on interpretation of traces results. Methodology/Principle findings We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d’Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Conclusions Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence
Enteric Neurospheres Are Not Specific to Neural Crest Cultures: Implications for Neural Stem Cell Therapies
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited
Being well, being musical: Music composition as a resource and occupation for older people
Introduction: Participatory music making for older people has tended to focus on singing and performance. In a community music project undertaken by Manchester Camerata (a chamber orchestra), Blacon Community Trust and a small group of older adults, participants were given the opportunity to compose individual pieces of music interactively with professional musicians. This paper reports the findings of the research project. Method: An arts-based research method was adopted and incorporated action research and interpretive interactionism to articulate the experiences and perceptions of participants. Participants and Manchester Camerata musicians also worked together to represent the thematic findings of the research in a group composition. Findings: The findings demonstrate that individual and group music composition contributed to a sense of wellbeing through control over musical materials, opportunities for creativity and identity making, validation of life experience and social engagement with other participants and professional musicians. Conclusion; The results emphasised occupation as essential to health and wellbeing in the later stages of life. The findings also highlight the particularly innovative aspects of this research: (i) the use of music composition as a viable arts-in-health occupation for older people and (ii) the arts-based research method of group composition. (PsycINFO Database Record (c) 2016 APA, all rights reserved
Comparison of cytokine and phosphoprotein profiles in idiopathic and Crohn's disease-related perianal fistula.
BACKGROUND: Perianal fistulae are either primary (idiopathic) or secondary [commonly associated with Crohn's disease, (CD)]. It is assumed, although not proven, that the pathophysiology differs. AIM: To systematically compare the clinical phenotypes, cytokine and phosphoprotein profiles of idiopathic and CD-related perianal fistulae. METHODS: Sixty-one patients undergoing surgery for perianal fistula were prospectively recruited (48 idiopathic, 13 CD) into a cohort study. Clinical data, including the Perineal Disease Activity Index (PDAI) and EQ-5D-5L were collected. Biopsies of the fistula tract, granulation tissue, internal opening mucosa and rectal mucosa were obtained at surgery. Concentrations of 30 cytokines and 39 phosphoproteins were measured in each biopsy using a magnetic bead multiplexing instrument and a chemiluminescent antibody array respectively. Over 12000 clinical and 23500 laboratory measurements were made. RESULTS: The PDAI was significantly higher (indicating more active disease) in the CD group with a mean difference of 2.40 (95%CI: 0.52-4.28, P = 0.01). Complex pathoanatomy was more prevalent in the CD group, namely more multiple fistulae, supralevator extensions, collections and rectal thickening. The IL-12p70 concentration at the internal opening specimen site was significantly higher (median difference 19.7 pg/mL, 99%CI: 0.2-40.4, P = 0.008) and the IL-1RA/IL-1β ratio was significantly lower in the CD group at the internal opening specimen site (median difference 15.0, 99%CI = 0.4-50.5, P = 0.008). However in the remaining 27 cytokines and all 39 of the phosphoproteins across the four biopsy sites, no significant differences were found between the groups. CONCLUSION: CD-related perianal fistulae are more clinically severe and anatomically complex than idiopathic perianal fistulae. However, overall there are no major differences in cytokine and phosphoprotein profiles
A secondary RET mutation in the activation loop conferring resistance to vandetanib
Resistance to vandetanib, a type I RET kinase inhibitor, developed in a patient with metastatic lung adenocarcinoma harboring a CCDC6-RET fusion that initially exhibited a response to treatment. The resistant tumor acquired a secondary mutation resulting in a serine-to-phenylalanine substitution at codon 904 in the activation loop of the RET kinase domain. The S904F mutation confers resistance to vandetanib by increasing the ATP affinity and autophosphorylation activity of RET kinase. A reduced interaction with the drug is also observed in vitro for the S904F mutant by thermal shift assay. A crystal structure of the S904F mutant reveals a small hydrophobic core around F904 likely to enhance basal kinase activity by stabilizing an active conformer. Our findings indicate that missense mutations in the activation loop of the kinase domain are able to increase kinase activity and confer drug resistance through allosteric effects
Strengthening patient-centred communication in rural Ugandan health centres: A theory-driven evaluation within a cluster randomized trial.
This article describes a theory-driven evaluation of one component of an intervention to improve the quality of health care at Ugandan public health centres. Patient-centred services have been advocated widely, but such approaches have received little attention in Africa. A cluster randomized trial is evaluating population-level outcomes of an intervention with multiple components, including 'patient-centred services.' A process evaluation was designed within this trial to articulate and evaluate the implementation and programme theories of the intervention. This article evaluates one hypothesized mechanism of change within the programme theory: the impact of the Patient Centred Services component on health-worker communication. The theory-driven approach extended to evaluation of the outcome measures. The study found that the proximal outcome of patient-centred communication was rated 10 percent higher (p < 0.008) by care seekers consulting with the health workers who were at the intervention health centres compared with those at control health centres. This finding will strengthen interpretation of more distal trial outcomes
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