69 research outputs found

    Biochemical and Structural Studies on Amyloid Aggregation in C. elegans

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    Organismal proteostasis is dependent on communication mechanisms such as stress responses. These multicellular organisms require intercellular stress responses which can act beyond the confines of individual cells to activate the proteostasis network (PN) across tissues to protect organismal health. One such mechanism is transcellular chaperone signalling (TCS). When proteostasis is compromised, misfolded proteins can accumulate, giving rise to detrimental conditions such as Alzheimer's disease, characterized by the aggregation of extracellular Aβ1-42 plaques in the human brain. TCS can be triggered by the tissue-specific over-expression or depletion of HSP- 90, which in turn activates distinct cell-non-autonomous signalling pathways. These pathways are instrumental in safeguarding entire organisms, such as the model organism C. elegans. The means by which this tissue-to-tissue communication enhances systemic chaperone expression and its potential to defend organisms against protein misfolding diseases remain unresolved questions. To shed light on this, C. elegans were used to investigate the mechanisms by which HSP-90 over-expression or depletion initiates TCS. This research revealed that over-expressing HSP-90 induces inter-tissue signalling from the intestine to neurons, thereby protecting against Aβ1-42 aggregation. Conversely, HSP-90 depletion in the intestine triggers TCS signalling to muscle cells, leading to the activation of HSP-70 expression, and aiding in TCS-mediated heat stress resistance and lifespan extension. The pathway identified highlights the role of 5 TXT-1 and CEH-58, a PDZ-domain guanylate cyclase and a homeobox transcription factor respectively, as peptides which stimulate extracellular peptides TXT-4 and TXT-8 to serve as trans-tissue signals to increase the HSP- 90 levels in distal tissues. To further explore Aβ1-42 aggregation in C. elegans, a workflow was developed to elucidate the in-tissue architecture of Aβ1-42 fibrils. This was achieved using advanced techniques such as cryogenic correlative light electron microscopy (cryo- CLEM) and cryogenic electron tomography (cryo-ET). Ultra-thin cryo-sections of adult C. elegans tissue were collected on cryo-EM grids, and cryo-CLEM was employed to accurately map the location of Aβ1-42 fibrils, providing precise guidance for the collection of cryo-ET data. The resulting 3D reconstructions unveiled the macromolecular features of adult C. elegans tissue and offered insights into the molecular architecture of Aβ1-42 fibrils. These fibrils were found to be organized into parallel bundles, in proximity to ribosomes and microtubules

    The in/exclusion and diagnosis of depression in patients with aphasia following stroke: A systematic review

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    Aphasia affects approximately a third of individuals who have a stroke and a similar proportion develop depression. Depression involves subjective symptoms (e.g. worthlessness) and its diagnosis conventionally relies on verbal interviews or rating scales, which is problematic if patients have aphasia. There is a large body of depression/stroke research. Our review of this literature aimed to systematically evaluate [1] the inclusion/exclusion of patients with aphasia and [2] the reporting and appropriateness of depression diagnostic methods used for patients with aphasia

    Does the Relationship between Age and Brain Structure Differ in Youth with Conduct Disorder?

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    Conduct disorder (CD) is characterised by persistent antisocial and aggressive behaviour and typically emerges in childhood or adolescence. Although several authors have proposed that CD is a neurodevelopmental disorder, very little evidence is available about brain development in this condition. Structural brain alterations have been observed in CD, and some indirect evidence for delayed brain maturation has been reported. However, no detailed analysis of age-related changes in brain structure in youth with CD has been conducted. Using cross-sectional MRI data, this study aimed to explore differences in brain maturation in youth with CD versus healthy controls to provide further understanding of the neurodevelopmental processes underlying CD. 291 CD cases (153 males) and 379 healthy controls (160 males) aged 9–18 years (Mage = 14.4) were selected from the European multisite FemNAT-CD study. Structural MRI scans were analysed using surface-based morphometry followed by application of the ENIGMA quality control protocols. An atlas-based approach was used to investigate group differences and test for group-by-age and group-by-age-by-sex interactions in cortical thickness, surface area and subcortical volumes. Relative to healthy controls, the CD group showed lower surface area across frontal, temporal and parietal regions as well as lower total surface area. No significant group-by-age or group-by-age-by-sex interactions were observed on any brain structure measure. These findings suggest that CD is associated with lower surface area across multiple cortical regions, but do not support the idea that CD is associated with delayed brain maturation, at least within the age bracket considered here.</p

    Allopurinol versus usual care in UK patients with ischaemic heart disease (ALL-HEART) : a multicentre, prospective, randomised, open-label, blinded-endpoint trial

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    Funding Information: ISM reports research grants from Menarini, EMA, Sanofi, Health Data Research UK, the British Heart Foundation, and Innovative Medicines Initiative; institutional consultancy income from AstraZeneca outside the submitted work; and personal income from AstraZeneca and Amgen outside the submitted work. TMM reports grants from Menarini/Ipsen/Teijin and Merck Sharp & Dohme outside the submitted work, and personal income for consultancy from Novartis and AstraZeneca outside the submitted work, and is a trustee of the Scottish Heart Arterial Risk Prevention Society. AGB reports personal income from Novartis, Mylan, AstraZeneca, Bayer, Daiichi-Sankyo, Boehringer, Pfizer, Galderma, Zambon, and Novo-Nordisk outside the submitted work. ADS and the University of Dundee hold a European patent for the use of xanthine oxidase inhibitors in treating chest pain in angina pectoris. AW declares personal income for consultancy from AbbVie, Akcea, Albireo, Alexion, Allergan, Amarin, Apsara, Arena, Astellas, AstraZeneca, Autolus, Bayer, Biocryst, Biogen, Biomarin, Bristol Myers Squibb, Boehringer Ingelheim, Calico, Celgene, Chiesi, Daiichi Sankyo, Diurnal, Elsai, Eli Lilly, Ferring, Galapagos, Gedeon Richter, Gilead, GlaxoSmithKline, GW Pharma, Idorsia, Incyte, Intercept, Ionis, Ipsen, Janssen, Jazz, Jcyte, Kite Gilead, LEK, Leo Pharma, Les Laboratoires Servier, Lundbeck, Merck (Merck Sharp & Dohme), Merck-Serono, Mitenyi, Mundibiopharma, Mustang Bio, Mylan, Myovant, Norgine, Novartis, Novo Nordisk, Orchard, Paion, Pfizer, Pierre Fabre, PTC, RegenXBio, Rhythm, Sanofi, Santen, Sarepta, SeaGen, Shionogi, Sigmatec, SOBI, Takeda, Tanaya, UCB, and Vertex outside the submitted work. JST declares research funding from the UK National Institute for Health and Care Research (NIHR) and NHS England outside the submitted work and membership of a UK National Institute for Health and Care Excellence guideline committee on management of atrial fibrillation. All other authors declare no competing interests. Funding Information: This study was funded by the NIHR Health Technology Assessment programme (HTA 11/36/41 to ISM, IF, CJH, LW, ADS, AGB, AJA, AW, JST, and TMM). The views expressed are those of the authors and not necessarily those of the NIHR or the UK Department of Health and Social Care. The study was supported by the Scottish Primary Care Research Network, Support for Science Scotland (Grampian, Highlands, Tayside, Fife, Forth Valley, Greater Glasgow and Clyde, Lothian, Ayrshire and Arran, Dumfries and Galloway, and Lanarkshire), and the NIHR Local Clinical Research Networks (East Midlands, West Midlands, Eastern, North Thames, Yorkshire and Humber, North East and North Cumbria, North West Coast, Kent, Surrey and Sussex, and South West Peninsula), which assisted with recruitment and other study activities. We thank Public Health Scotland and NHS Digital for providing data linkage. We thank all the participants, physicians, nurses, and other staff who participated in the ALL-HEART study. Funding Information: This study was funded by the NIHR Health Technology Assessment programme (HTA 11/36/41 to ISM, IF, CJH, LW, ADS, AGB, AJA, AW, JST, and TMM). The views expressed are those of the authors and not necessarily those of the NIHR or the UK Department of Health and Social Care. The study was supported by the Scottish Primary Care Research Network, Support for Science Scotland (Grampian, Highlands, Tayside, Fife, Forth Valley, Greater Glasgow and Clyde, Lothian, Ayrshire and Arran, Dumfries and Galloway, and Lanarkshire), and the NIHR Local Clinical Research Networks (East Midlands, West Midlands, Eastern, North Thames, Yorkshire and Humber, North East and North Cumbria, North West Coast, Kent, Surrey and Sussex, and South West Peninsula), which assisted with recruitment and other study activities. We thank Public Health Scotland and NHS Digital for providing data linkage. We thank all the participants, physicians, nurses, and other staff who participated in the ALL-HEART study. Publisher Copyright: © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licensePeer reviewedPublisher PD

    Age-Dependent Maturation of Toll-Like Receptor-Mediated Cytokine Responses in Gambian Infants

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    The global burden of neonatal and infant mortality due to infection is staggering, particularly in resource-poor settings. Early childhood vaccination is one of the major interventions that can reduce this burden, but there are specific limitations to inducing effective immunity in early life, including impaired neonatal leukocyte production of Th1-polarizing cytokines to many stimuli. Characterizing the ontogeny of Toll-like receptor (TLR)-mediated innate immune responses in infants may shed light on susceptibility to infection in this vulnerable age group, and provide insights into TLR agonists as candidate adjuvants for improved neonatal vaccines. As little is known about the leukocyte responses of infants in resource-poor settings, we characterized production of Th1-, Th2-, and anti-inflammatory- cytokines in response to agonists of TLRs 1-9 in whole blood from 120 Gambian infants ranging from newborns (cord blood) to 12 months of age. Most of the TLR agonists induced TNFα, IL-1β, IL-6, and IL-10 in cord blood. The greatest TNFα responses were observed for TLR4, -5, and -8 agonists, the highest being the thiazoloquinoline CLO75 (TLR7/8) that also uniquely induced cord blood IFNγ production. For most agonists, TLR-mediated TNFα and IFNγ responses increased from birth to 1 month of age. TLR8 agonists also induced the greatest production of the Th1-polarizing cytokines TNFα and IFNγ throughout the first year of life, although the relative responses to the single TLR8 agonist and the combined TLR7/8 agonist changed with age. In contrast, IL-1β, IL-6, and IL-10 responses to most agonists were robust at birth and remained stable through 12 months of age. These observations provide fresh insights into the ontogeny of innate immunity in African children, and may inform development of age-specific adjuvanted vaccine formulations important for global health

    Allopurinol versus usual care in UK patients with ischaemic heart disease (ALL-HEART): a multicentre, prospective, randomised, open-label, blinded-endpoint trial

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    BACKGROUND: Allopurinol is a urate-lowering therapy used to treat patients with gout. Previous studies have shown that allopurinol has positive effects on several cardiovascular parameters. The ALL-HEART study aimed to determine whether allopurinol therapy improves major cardiovascular outcomes in patients with ischaemic heart disease. METHODS: ALL-HEART was a multicentre, prospective, randomised, open-label, blinded-endpoint trial done in 18 regional centres in England and Scotland, with patients recruited from 424 primary care practices. Eligible patients were aged 60 years or older, with ischaemic heart disease but no history of gout. Participants were randomly assigned (1:1), using a central web-based randomisation system accessed via a web-based application or an interactive voice response system, to receive oral allopurinol up-titrated to a dose of 600 mg daily (300 mg daily in participants with moderate renal impairment at baseline) or to continue usual care. The primary outcome was the composite cardiovascular endpoint of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. The hazard ratio (allopurinol vs usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis (excluding randomly assigned patients later found to have met one of the exclusion criteria). The safety analysis population included all patients in the modified intention-to-treat usual care group and those who took at least one dose of randomised medication in the allopurinol group. This study is registered with the EU Clinical Trials Register, EudraCT 2013-003559-39, and ISRCTN, ISRCTN32017426. FINDINGS: Between Feb 7, 2014, and Oct 2, 2017, 5937 participants were enrolled and then randomly assigned to receive allopurinol or usual care. After exclusion of 216 patients after randomisation, 5721 participants (mean age 72·0 years [SD 6·8], 4321 [75·5%] males, and 5676 [99·2%] white) were included in the modified intention-to-treat population, with 2853 in the allopurinol group and 2868 in the usual care group. Mean follow-up time in the study was 4·8 years (1·5). There was no evidence of a difference between the randomised treatment groups in the rates of the primary endpoint. 314 (11·0%) participants in the allopurinol group (2·47 events per 100 patient-years) and 325 (11·3%) in the usual care group (2·37 events per 100 patient-years) had a primary endpoint (hazard ratio [HR] 1·04 [95% CI 0·89–1·21], p=0·65). 288 (10·1%) participants in the allopurinol group and 303 (10·6%) participants in the usual care group died from any cause (HR 1·02 [95% CI 0·87–1·20], p=0·77). INTERPRETATION: In this large, randomised clinical trial in patients aged 60 years or older with ischaemic heart disease but no history of gout, there was no difference in the primary outcome of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death between participants randomised to allopurinol therapy and those randomised to usual care. FUNDING: UK National Institute for Health and Care Research

    Hope and despair: a qualitative exploration of the expereinces and impact of trial processes in a rehabilitation trial

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    Background Unanticipated responses by research participants can influence randomised controlled trials (RCTs) in multiple ways, many of which are poorly understood. This study used qualitative interviews as part of an embedded process evaluation to explore the impact participants may have on the study, but also unintended impacts the study may have on them. Aim The aim of the study was to explore participants’ experiences and the impact of trial involvement in a pilot RCT in order to inform the designing and delivery of a definitive RCT. Methods In-depth interviews with 20 participants (10 in the intervention and 10 in the control group) enrolled in a stroke rehabilitation pilot trial. A modified framework approach was used to analyse transcripts. Results Participation in the study was motivated partly by a desperation to receive further rehabilitation after discharge. Responses to allocation to the control group included an increased commitment to self-treatment, and negative psychological consequences were also described. Accounts of participants in both control and intervention groups challenge the presumption that they were neutral, or in equipoise, regarding group allocation prior to consenting to randomisation. Conclusions Considering and exploring participant and participation effects, particularly in the control group, highlights numerous issues in the interpretation of trial studies, as well as the in ethics of RCTs more generally. While suggestions for a definitive trial design are given, further research is required to investigate the significant implications these findings may have for trial design, monitoring and funding. Trial registration ClinicalTrials.gov, NCT02429180. Registered on 29 April/2015.The Stroke Associatio

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

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    Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
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