103 research outputs found

    Human candidate gene polymorphisms and risk of severe malaria in children in Kilifi, Kenya: a case-control association study

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    Background: Human genetic factors are important determinants of malaria risk. We investigated associations between multiple candidate polymorphisms—many related to the structure or function of red blood cells—and risk for severe Plasmodium falciparum malaria and its specific phenotypes, including cerebral malaria, severe malaria anaemia, and respiratory distress. Methods: We did a case-control study in Kilifi County, Kenya. We recruited as cases children presenting with severe malaria to the high-dependency ward of Kilifi County Hospital. We included as controls infants born in the local community between Aug 1, 2006, and Sept 30, 2010, who were part of a genetics study. We tested for associations between a range of candidate malaria-protective genes and risk for severe malaria and its specific phenotypes. We used a permutation approach to account for multiple comparisons between polymorphisms and severe malaria. We judged p values less than 0·005 significant for the primary analysis of the association between candidate genes and severe malaria. Findings: Between June 11, 1995, and June 12, 2008, 2244 children with severe malaria were recruited to the study, and 3949 infants were included as controls. Overall, 263 (12%) of 2244 children with severe malaria died in hospital, including 196 (16%) of 1233 with cerebral malaria. We investigated 121 polymorphisms in 70 candidate severe malaria-associated genes. We found significant associations between risk for severe malaria overall and polymorphisms in 15 genes or locations, of which most were related to red blood cells: ABO, ATP2B4, ARL14, CD40LG, FREM3, INPP4B, G6PD, HBA (both HBA1 and HBA2), HBB, IL10, LPHN2 (also known as ADGRL2), LOC727982, RPS6KL1, CAND1, and GNAS. Combined, these genetic associations accounted for 5·2% of the variance in risk for developing severe malaria among individuals in the general population. We confirmed established associations between severe malaria and sickle-cell trait (odds ratio [OR] 0·15, 95% CI 0·11–0·20; p=2·61 × 10−58), blood group O (0·74, 0·66–0·82; p=6·26 × 10−8), and –α3·7-thalassaemia (0·83, 0·76–0·90; p=2·06 × 10−6). We also found strong associations between overall risk of severe malaria and polymorphisms in both ATP2B4 (OR 0·76, 95% CI 0·63–0·92; p=0·001) and FREM3 (0·64, 0·53–0·79; p=3·18 × 10−14). The association with FREM3 could be accounted for by linkage disequilibrium with a complex structural mutation within the glycophorin gene region (comprising GYPA, GYPB, and GYPE) that encodes for the rare Dantu blood group antigen. Heterozygosity for Dantu was associated with risk for severe malaria (OR 0·57, 95% CI 0·49–0·68; p=3·22 × 10−11), as was homozygosity (0·26, 0·11–0·62; p=0·002). Interpretation: Both ATP2B4 and the Dantu blood group antigen are associated with the structure and function of red blood cells. ATP2B4 codes for plasma membrane calcium-transporting ATPase 4 (the major calcium pump on red blood cells) and the glycophorins are ligands for parasites to invade red blood cells. Future work should aim at uncovering the mechanisms by which these polymorphisms can result in severe malaria protection and investigate the implications of these associations for wider health. Funding: Wellcome Trust, UK Medical Research Council, European Union, and Foundation for the National Institutes of Health as part of the Bill & Melinda Gates Grand Challenges in Global Health Initiative

    ANCA-associated renal vasculitis is associated with rurality but not seasonality or deprivation in a complete national cohort study

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    Background Small studies suggest an association between ANCA-associated vasculitis (AAV) incidence and rurality, seasonality and socioeconomic deprivation. We examined the incidence of kidney biopsy-proven AAV and its relationship with these factors in the adult Scottish population.Methods Using the Scottish Renal Biopsy Registry, all adult native kidney biopsies performed between 2014 and 2018 with a diagnosis of granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) were identified. The Scottish Government Urban Rural Classification was used for rurality analysis. Seasons were defined as autumn (September–November), winter (December–February), spring (March–May) and summer (June–August). Patients were separated into quintiles of socioeconomic deprivation using the validated Scottish Index of Multiple Deprivation and incidence standardised to age. Estimated glomerular filtration rate and urine protein:creatinine ratio at time of biopsy were used to assess disease severity.Results 339 cases of renal AAV were identified, of which 62% had MPA and 38% had GPA diagnosis. AAV incidence was 15.1 per million population per year (pmp/year). Mean age was 66 years and 54% were female. Incidence of GPA (but not MPA) was positively associated with rurality (5.2, 8.4 and 9.1 pmp/year in ‘urban’, ‘accessible remote’ and ‘rural remote’ areas, respectively; p=0.04). The age-standardised incidence ratio was similar across all quintiles of deprivation (p=ns).Conclusions Seasonality and disease severity did not vary across AAV study groups. In this complete national cohort study, we observed a positive association between kidney biopsy-proven GPA and rurality

    Public engagement on global health challenges

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    <p>Abstract</p> <p>Background</p> <p>Experience with public engagement activities regarding the risks and benefits of science and technology (S&T) is growing, especially in the industrialized world. However, public engagement in the developing world regarding S&T risks and benefits to explore health issues has not been widely explored.</p> <p>Methods</p> <p>This paper gives an overview about public engagement and related concepts, with a particular focus on challenges and benefits in the developing world. We then describe an Internet-based platform, which seeks to both inform and engage youth and the broader public on global water issues and their health impacts. Finally, we outline a possible course for future action to scale up this and similar online public engagement platforms.</p> <p>Results</p> <p>The benefits of public engagement include creating an informed citizenry, generating new ideas from the public, increasing the chances of research being adopted, increasing public trust, and answering ethical research questions. Public engagement also fosters global communication, enables shared experiences and methodology, standardizes strategy, and generates global viewpoints. This is especially pertinent to the developing world, as it encourages previously marginalized populations to participate on a global stage. One of the core issues at stake in public engagement is global governance of science and technology. Also, beyond benefiting society at large, public engagement in science offers benefits to the scientific enterprise itself.</p> <p>Conclusion</p> <p>Successful public engagement with developing world stakeholders will be a critical part of implementing new services and technologies. Interactive engagement platforms, such as the Internet, have the potential to unite people globally around relevant health issues.</p

    Substrate Trapping Proteomics Reveals Targets of the βTrCP2/FBXW11 Ubiquitin Ligase

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    Defining the full complement of substrates for each ubiquitin ligase remains an important challenge. Improvements in mass spectrometry instrumentation and computation and in protein biochemistry methods have resulted in several new methods for ubiquitin ligase substrate identification. Here we used the parallel adapter capture (PAC) proteomics approach to study βTrCP2/FBXW11, a substrate adaptor for the SKP1–CUL1–F-box (SCF) E3 ubiquitin ligase complex. The processivity of the ubiquitylation reaction necessitates transient physical interactions between FBXW11 and its substrates, thus making biochemical purification of FBXW11-bound substrates difficult. Using the PAC-based approach, we inhibited the proteasome to “trap” ubiquitylated substrates on the SCFFBXW11E3 complex. Comparative mass spectrometry analysis of immunopurified FBXW11 protein complexes before and after proteasome inhibition revealed 21 known and 23 putatively novel substrates. In focused studies, we found that SCFFBXW11bound, polyubiquitylated, and destabilized RAPGEF2, a guanine nucleotide exchange factor that activates the small GTPase RAP1. High RAPGEF2 protein levels promoted cell-cell fusion and, consequently, multinucleation. Surprisingly, this occurred independently of the guanine nucleotide exchange factor (GEF) catalytic activity and of the presence of RAP1. Our data establish new functions for RAPGEF2 that may contribute to aneuploidy in cancer. More broadly, this report supports the continued use of substrate trapping proteomics to comprehensively define targets for E3 ubiquitin ligases. All proteomic data are available via ProteomeXchange with identifier PXD001062

    Antral atrophy, intestinal metaplasia, and preneoplastic markers in Mexican children with Helicobacter pylori–positive and Helicobacter pylori–negative gastritis

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    Chronic inflammation and infection are major risk factors for gastric carcinogenesis in adults. As chronic gastritis is common in Mexican children, diagnosis of Helicobacter pylori and other causes of gastritis are critical for the identification of children who would benefit from closer surveillance. Antral biopsies from 82 Mexican children (mean age 8.3±4.8y) with chronic gastritis (36 H. pylori +, 46 H. pylori -) were examined for gastritis activity, atrophy, intestinal metaplasia, and immunohistochemical expression of gastric carcinogenesis biomarkers CDX2, ephrin type-B receptor 4, matrix metalloproteinase 3 (MMP3), macrophage migration inhibitory factor (MIF), p53, β-catenin, and E-cadherin. Atrophy was diagnosed in 7/82 (9%) and intestinal metaplasia in 5/82 (6%) by routine histology, while 6 (7%) additional children (3 H. pylori +) exhibited aberrant CDX2 expression without intestinal metaplasia. Significant positive correlations were seen between EphB4, MMP3, and MIF (p<0.0001). Atrophy and follicular pathology were more frequent in H. pylori + biopsies (p<0.0001), while intestinal metaplasia and CDX2 expression showed no significant correlation with H. pylori status. Antral biopsies demonstrating atrophy, intestinal metaplasia, and/or aberrant CDX2 expression were seen in 21.95 % (18/82) of the children, potentially identifying those who would benefit from closer surveillance and preventive dietary strategies. Biomarkers CDX2, EphB4, MMP3, and MIF may be useful in the work-up of pediatric gastritis

    Environmental interactions of tidal lagoons: A comparison of industry perspectives

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    Tidal lagoons are an attractive renewable energy option that could aid the UK in meeting its ambitious renewable energy targets. One of the main barriers to tidal range development in the UK to date has been regulatory environmental concern. In order for the nascent lagoon industry to move forward into development, the views of the developers and other influential stakeholders such as government bodies, regulators, conservationists and practitioners (herein referred to as 'influencing stakeholders' or 'influencers') need to be aligned. This study is the first of its kind using online questionnaires and semi-structured interviews to present and compare the views of both developers and influencing stakeholders on the environmental interactions of tidal lagoons. We find that, whilst both influencers and developers are working towards the common goal of a good environmental outcome for tidal lagoons, there are mismatches in their views in terms of the priorities given to the key environmental impacts, benefits and potential solution options. The work provides insight into what is at the forefront of developers' and influencers' minds, highlighting the key themes within their views and transforming this information into policy recommendations that will help the industry's development move forward

    Transcriptional profiling of the ovine abomasal lymph node reveals a role for timing of the immune response in gastrointestinal nematode resistance

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    Gastrointestinal nematodes are a serious cause of morbidity and mortality in grazing ruminants. The major ovine defence mechanism is acquired immunity, with protective immunity developing over time in response to infection. Nematode resistance varies both within and between breeds and is moderately heritable. A detailed understanding of the genes and mechanisms involved in protective immunity, and the factors that regulate this response, is required to aid both future breeding strategies and the development of effective and sustainable nematode control methods. The aim of this study was to compare the abomasal lymph node transcriptome of resistant and susceptible lambs in order to determine biological processes differentially expressed between resistant and susceptible individuals. Scottish Blackface lambs, with divergent phenotypes for resistance, were challenged with 30,000 Teladorsagia circumcincta larvae (L3), and abomasal lymph nodes recovered at 7 and 14 days post-infection (dpi). High-throughput sequencing of cDNA from the abomasal lymph node was used to quantitatively sample the transcriptome with an average of 32 million reads per sample. A total of 194 and 144 genes were differentially expressed between resistant and susceptible lambs at 7 and 14 dpi respectively. Differentially expressed networks and biological processes were identified using Ingenuity Pathway Analysis. Genes involved in the inflammatory response, attraction of T lymphocytes and binding of leukocytes were more highly expressed in resistant animals at 7 dpi and in susceptible animals at 14 dpi indicating that resistant animals respond to infection earlier than susceptible animals. Twenty-four Single Nucleotide Polymorphisms (SNP) within 11 differentially expressed genes, were tested for association with gastrointestinal nematode resistance in the Scottish Blackface lambs. Four SNP, in 2 genes (SLC30A2 and ALB), were suggestively associated with faecal egg count. In conclusion, a large number of genes were differentially expressed in the abomasal lymph node of resistant and susceptible lambs responding to gastrointestinal nematode challenge. Resistant Scottish Blackface lambs appear to generate an earlier immune response to T. circumcincta. In susceptible lambs this response appears to be delayed. SNP in 2 differentially expressed genes were suggestively associated with faecal egg count indicating that differentially expressed genes may be considered candidate loci for mediating nematode resistance

    Improving physical health and reducing substance use in psychosis - randomised control trial (IMPACT RCT): study protocol for a cluster randomised controlled trial

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    The National Institute for Health Research funds the IMPACT programme at King’s College London and South London and Maudsley NHS Foundation Trust (ref: RP-PG-0606-1049)

    SlowMo, a digital therapy targeting reasoning in paranoia, versus treatment as usual in the treatment of people who fear harm from others: study protocol for a randomised controlled trial

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    Background: Paranoia is one of the most common symptoms of schizophrenia-spectrum disorders, and is associated with significant distress and disruption to the person’s life. Developing more effective and accessible psychological interventions for paranoia is a clinical priority. Our research team has approached this challenge in two main ways: firstly, by adopting an interventionist causal approach to increase effectiveness and secondly, by incorporating user-centred inclusive design methods to enhance accessibility and usability. Our resultant new digital intervention, SlowMo, intensively targets a reasoning style associated with paranoia, fast thinking, characterised by jumping to conclusions and belief inflexibility. It consists of an easy-to-use, enjoyable and memorable digital interface. An interactive web-based app facilitates delivery of face-to-face meetings which is then synchronised with an innovative mobile app for use in daily life. Methods/Design: We aim to test the clinical efficacy of SlowMo over 24 weeks to determine the mechanisms through which it reduces paranoia, and to identify participant characteristics that moderate its effectiveness. In a parallel-group randomised controlled trial, with 1:1 allocation, 360 participants with distressing persecutory beliefs will be independently randomised to receive either the SlowMo intervention added to treatment as usual (TAU) or TAU, using randomly varying permuted blocks, stratified by paranoia severity and site. Research workers will be blind to therapy allocation. The primary outcome is paranoia severity over 24 weeks; our hypothesised mechanism of change is reasoning; moderators include negative symptoms and working memory; and secondary outcomes include wellbeing, quality of life, and service use. The accessibility, usability and acceptability of the digital platform will be assessed. Discussion: SlowMo has been developed as the first blended digital therapy to target fears of harm from others through an inclusive design approach. In addition to testing its efficacy, this trial will add to our understanding of psychological mechanisms in paranoia. The study will examine the usability and adherence of a novel digital therapy, including an app for self-management, in a large sample of people affected by severe mental health difficulties
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