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Professor Daniel Freeman, Department of Psychiatry, presented a new ten-part BBC Radio 4 series called 'A History of Delusions'.
Challenges and solutions to system-wide use of precision oncology as the standard of care paradigm.
The personalised oncology paradigm remains challenging to deliver despite technological advances in genomics-based identification of actionable variants combined with the increasing focus of drug development on these specific targets. To ensure we continue to build concerted momentum to improve outcomes across all cancer types, financial, technological and operational barriers need to be addressed. For example, complete integration and certification of the 'molecular tumour board' into 'standard of care' ensures a unified clinical decision pathway that both counteracts fragmentation and is the cornerstone of evidence-based delivery inside and outside of a research setting. Generally, integrated delivery has been restricted to specific (common) cancer types either within major cancer centres or small regional networks. Here, we focus on solutions in real-world integration of genomics, pathology, surgery, oncological treatments, data from clinical source systems and analysis of whole-body imaging as digital data that can facilitate cost-effectiveness analysis, clinical trial recruitment, and outcome assessment. This urgent imperative for cancer also extends across the early diagnosis and adjuvant treatment interventions, individualised cancer vaccines, immune cell therapies, personalised synthetic lethal therapeutics and cancer screening and prevention. Oncology care systems worldwide require proactive step-changes in solutions that include inter-operative digital working that can solve patient centred challenges to ensure inclusive, quality, sustainable, fair and cost-effective adoption and efficient delivery. Here we highlight workforce, technical, clinical, regulatory and economic challenges that prevent the implementation of precision oncology at scale, and offer a systematic roadmap of integrated solutions for standard of care based on minimal essential digital tools. These include unified decision support tools, quality control, data flows within an ethical and legal data framework, training and certification, monitoring and feedback. Bridging the technical, operational, regulatory and economic gaps demands the joint actions from public and industry stakeholders across national and global boundaries.
Structural and functional characterization of nanobodies that neutralize Omicron variants of SARS-CoV-2.
The Omicron strains of SARS-CoV-2 pose a significant challenge to the development of effective antibody-based treatments as immune evasion has compromised most available immune therapeutics. Therefore, in the 'arms race' with the virus, there is a continuing need to identify new biologics for the prevention or treatment of SARS-CoV-2 infections. Here, we report the isolation of nanobodies that bind to the Omicron BA.1 spike protein by screening nanobody phage display libraries previously generated from llamas immunized with either the Wuhan or Beta spike proteins. The structure and binding properties of three of these nanobodies (A8, H6 and B5-5) have been characterized in detail providing insight into their binding epitopes on the Omicron spike protein. Trimeric versions of H6 and B5-5 neutralized the SARS-CoV-2 variant of concern BA.5 both in vitro and in the hamster model of COVID-19 following nasal administration. Thus, either alone or in combination could serve as starting points for the development of new anti-viral immunotherapeutics.
Positive feedbacks and alternative stable states in forest leaf types.
The emergence of alternative stable states in forest systems has significant implications for the functioning and structure of the terrestrial biosphere, yet empirical evidence remains scarce. Here, we combine global forest biodiversity observations and simulations to test for alternative stable states in the presence of evergreen and deciduous forest types. We reveal a bimodal distribution of forest leaf types across temperate regions of the Northern Hemisphere that cannot be explained by the environment alone, suggesting signatures of alternative forest states. Moreover, we empirically demonstrate the existence of positive feedbacks in tree growth, recruitment and mortality, with trees having 4-43% higher growth rates, 14-17% higher survival rates and 4-7 times higher recruitment rates when they are surrounded by trees of their own leaf type. Simulations show that the observed positive feedbacks are necessary and sufficient to generate alternative forest states, which also lead to dependency on history (hysteresis) during ecosystem transition from evergreen to deciduous forests and vice versa. We identify hotspots of bistable forest types in evergreen-deciduous ecotones, which are likely driven by soil-related positive feedbacks. These findings are integral to predicting the distribution of forest biomes, and aid to our understanding of biodiversity, carbon turnover, and terrestrial climate feedbacks.
Post-traumatic stress disorder symptoms following exposure to acute psychological trauma in children aged 8-16 years in South Africa: protocol for the Sinethemba longitudinal study
Abstract Introduction Children exposed to trauma are vulnerable to developing posttraumatic stress disorder (PTSD) and other adverse mental health outcomes. In low-and-middle-income countries (LMICs), children are at increased risk of exposure to severe trauma and co-occurring adversities. However, relative to high income countries, there is limited evidence of the factors that predict good versus poor psychological recovery following trauma exposure in LMIC children, and the role of caregiver support in these high-adversity communities. Methods and analysis We will conduct a longitudinal, observational study of 250 children aged 8-16 years and their caregivers in South Africa, following child exposure to acute trauma. Dyads will be recruited from community hospitals following a potentially traumatic event, such as a motor vehicle accident or assault. Potential participants will be identified during their hospital visit, and if they agree, will subsequently be contacted by study researchers. Assessments will take place within 4 weeks of the traumatic event, with 3-month and 6-month follow-up assessments. Participants will provide a narrative description of the traumatic event and complete questionnaires designed to give information about social and psychological risk factors. Child PTSD symptoms will be the primary outcome, and wider trauma-related mental health (depression, anxiety, behavioral problems) will be secondary outcomes. Regression-based methods will be used to examine the association of psychosocial factors in the acute phase following trauma, including caregiver support and responding, with child PTSD and wider mental health outcomes. Ethics and dissemination Ethical approvals have been granted by Stellenbosch University and the University of Bath, with additional to recruit via hospitals and healthcare clinics being granted by the University of Cape Town, the Department of Health, and the City of Cape Town. Study findings will be disseminated via publication in journals, workshops for practitioners and policymakers, and public engagement events. Strengths and Limitations • Longitudinal methods were piloted in settlement communities of Cape Town, enabling strong links to be established with proposed recruitment sites. • Focus groups have been conducted with members of the community to ensure proposed study methods and materials are culturally sensitive. • Pilot work has demonstrated excellent retention rates, however some missing data will be expected due to study participant attrition. This will be managed using multiple imputation methods during analysis. • A limited set of biological samples will be collected, including heart rate data and dried blood spot samples. This will allow a robust examination of the biological predictors of childhood PTSD whilst maximizing study acceptability.
Multilevel sociality in the spotted hyaena: How to live in large groups without falling prey to the infertility trap
Spotted hyaenas live in unusually large social groups for a carnivore. Since, all else equal, the ‘infertility trap’ (a negative relationship between fertility and the number of females in a group) limits social group sizes to ~5 reproductive females in mammals, hyaena must, like other very social species, have found a way to mitigate the stresses involved in order to do so. From a comparative analysis of data from 19 well-studied Crocuta crocuta populations, I show (1) that the distribution of hyaena clan sizes is multimodal, with a fractal scaling ratio close to 3 and a base unit of 12–15 individuals (3–5 reproductive females), (2) that fertility is a negative function of number of females in the group and (3) that there is a trade-off between the benefits of having more males in the group and the costs incurred by having more females. Although females do buffer themselves against the infertility trap by forming matrilineal alliances (thereby creating a primate-like multilevel structure), males seem to play an important role, such that, in areas with a low density of males, clan sizes are much smaller.
Longitudinal alcohol-related brain changes in older adults: The Sydney Memory and Ageing Study.
Increases in harmful drinking among older adults indicate the need for a more thorough understanding of the relationship between later-life alcohol use and brain health. The current study investigated the relationships between alcohol use and progressive grey and white matter changes in older adults using longitudinal data. A total of 530 participants (aged 70 to 90 years; 46.0% male) were included. Brain outcomes assessed over 6 years included total grey and white matter volume, as well as volume of the hippocampus, thalamus, amygdala, corpus callosum, orbitofrontal cortex and insula. White matter integrity was also investigated. Average alcohol use across the study period was the main exposure of interest. Past-year binge drinking and reduction in drinking from pre-baseline were additional exposures of interest. Within the context of low-level average drinking (averaging 11.7 g per day), higher average amount of alcohol consumed was associated with less atrophy in the left (B = 7.50, pFDR = 0.010) and right (B = 5.98, pFDR = 0.004) thalamus. Past-year binge-drinking was associated with poorer white matter integrity (B = -0.013, pFDR = 0.024). Consuming alcohol more heavily in the past was associated with greater atrophy in anterior (B = -12.73, pFDR = 0.048) and posterior (B = -17.88, pFDR = 0.004) callosal volumes over time. Across alcohol exposures and neuroimaging markers, no other relationships were statistically significant. Within the context of low-level drinking, very few relationships between alcohol use and brain macrostructure were identified. Meanwhile, heavier drinking was negatively associated with white matter integrity.
Identifying characteristics that enable resilient immunisation programmes: a scoping review.
OBJECTIVES: The COVID-19 pandemic highlighted the fragility of immunisation programmes and resulted in a significant reduction in vaccination rates, with increasing vaccine-preventable disease outbreaks consequently reported. These vulnerabilities underscore the importance of resilient immunisation programmes to ensure optimal performance during crises. To date, a framework for assessing immunisation programme resilience does not exist. We conducted a scoping review of immunisation programmes during times of crisis to identify factors that characterise resilient immunisation programmes, which may inform an Immunisation Programme Resilience Tool. DESIGN: Scoping review design followed the Arksey and O'Malley framework, and manuscript reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews guidelines. DATA SOURCES: CINAHL, CENTRAL, Embase, Google Scholar, MEDLINE, PsycINFO and Web of Science and databases were searched between 1 January 2011 and 2 September 2023. Citation searching of identified studies was also performed. ELIGIBILITY CRITERIA: We included primary empirical peer-reviewed studies that discussed the resilience of immunisation programme to crises, shocks or disruptions. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers screened records and performed data extraction. We extracted data on study location and design, crisis description, and resilience characteristics discussed, and identified evidence gaps in the literature. Findings were synthesised using tabulation and an evidence gap map. RESULTS: Thirty-seven studies met the eligibility criteria. These studies captured research conducted across six continents, with most concentrated in Africa, Asia and Europe. One study had a randomised controlled trial design, while 36 studies had observational designs (15 analytical and 21 descriptive). We identified five characteristics of resilient immunisation programmes drawing on the Health System Resilience Index (Integration, Awareness, Resource Availability and Access, Adaptiveness and Self-regulation) and several evidence gaps in the literature. CONCLUSIONS: To our knowledge, no immunisation programme resilience tool exists. We identified factors from the Health System Resilience Index coupled with factors identified through primary empirical evidence, which may inform development of an immunisation programme resilience tool.
Advances and challenges in modeling inherited peripheral neuropathies using iPSCs.
Inherited peripheral neuropathies (IPNs) are a group of diseases associated with mutations in various genes with fundamental roles in the development and function of peripheral nerves. Over the past 10 years, significant advances in identifying molecular disease mechanisms underlying axonal and myelin degeneration, acquired from cellular biology studies and transgenic fly and rodent models, have facilitated the development of promising treatment strategies. However, no clinical treatment has emerged to date. This lack of treatment highlights the urgent need for more biologically and clinically relevant models recapitulating IPNs. For both neurodevelopmental and neurodegenerative diseases, patient-specific induced pluripotent stem cells (iPSCs) are a particularly powerful platform for disease modeling and preclinical studies. In this review, we provide an update on different in vitro human cellular IPN models, including traditional two-dimensional monoculture iPSC derivatives, and recent advances in more complex human iPSC-based systems using microfluidic chips, organoids, and assembloids.
Bayliss Starling Prize Lecture 2023: Neuropeptide-Y being 'unsympathetic' to the broken hearted.
William Bayliss and Ernest Starling are not only famous as pioneers in cardiovascular physiology, but also responsible for the discovery of the first hormone (from the Greek 'excite or arouse'), the intestinal signalling molecule and neuropeptide secretin in 1902. Our research group focuses on neuropeptides and neuromodulators that influence cardiovascular autonomic control as potential biomarkers in disease and tractable targets for therapeutic intervention. Acute myocardial infarction (AMI) and chronic heart failure (CHF) result in high levels of cardiac sympathetic stimulation, which is a poor prognostic indicator. Although beta-blockers improve mortality in these conditions by preventing the action of the neurotransmitter noradrenaline, a substantial residual risk remains. Recently, we have identified the sympathetic co-transmitter neuropeptide-Y (NPY) as being released during AMI, leading to larger infarcts and life-threatening arrhythmia in both animal models and patients. Here, we discuss recently published data demonstrating that peripheral venous NPY levels are associated with heart failure hospitalisation and mortality after AMI, and all cause cardiovascular mortality in CHF, even when adjusting for known risk factors (including brain natriuretic peptide). We have investigated the mechanistic basis for these observations in human and rat stellate ganglia and cardiac tissue, manipulating NPY neurochemistry at the same time as using state-of-the-art imaging techniques, to establish the receptor pathways responsible for NPY signalling. We propose NPY as a new mechanistic biomarker in AMI and CHF patients and aim to determine whether specific NPY receptor blockers can prevent arrhythmia and attenuate the development of heart failure.
In Silico CRISPR-Cas-Mediated Base Editing Strategies for Early-Onset, Severe Cone-Rod Retinal Degeneration in Three Crumbs homolog 1 Patients, including the Novel Variant c.2833G>A.
Pathogenic variants in the Crumbs homolog 1 (CRB1) gene lead to severe, childhood-onset retinal degeneration leading to blindness in early adulthood. There are no approved therapies, and traditional adeno-associated viral vector-based gene therapy approaches are challenged by the existence of multiple CRB1 isoforms. Here, we describe three CRB1 variants, including a novel, previously unreported variant that led to retinal degeneration. We offer a CRISPR-Cas-mediated DNA base editing strategy as a potential future therapeutic approach. This study is a retrospective case series. Clinical and genetic assessments were performed, including deep phenotyping by retinal imaging. In silico analyses were used to predict the pathogenicity of the novel variant and to determine whether the variants are amenable to DNA base editing strategies. Case 1 was a 24-year-old male with cone-rod dystrophy and retinal thickening typical of CRB1 retinopathy. He had a relatively preserved central outer retinal structure and a best corrected visual acuity (BCVA) of 60 ETDRS letters in both eyes. Genetic testing revealed compound heterozygous variants in exon 9: c.2843G>A, p.(Cys948Tyr) and a novel variant, c.2833G>A, p.(Gly945Arg), which was predicted to likely be pathogenic by an in silico analysis. Cases 2 and 3 were two brothers, aged 20 and 24, who presented with severe cone-rod dystrophy and a significant disruption of the outer nuclear layers. The BCVA was reduced to hand movements in both eyes in Case 2 and to 42 ETDRS letters in both eyes in Case 3. Case 2 was also affected with marked cystoid macular lesions, which are common in CRB1 retinopathy, but responded well to treatment with oral acetazolamide. Genetic testing revealed two c.2234C>T, p.(Thr745Met) variants in both brothers. As G-to-A and C-to-T variants, all three variants are amenable to adenine base editors (ABEs) targeting the forward strand in the Case 1 variants and the reverse strand in Cases 2 and 3. Available PAM sites were detected for KKH-nSaCas9-ABE8e for the c.2843G>A variant, nSaCas9-ABE8e and KKH-nSaCas9-ABE8e for the c.2833G>A variant, and nSpCas9-ABE8e for the c.2234C>T variant. In this case series, we report three pathogenic CRB1 variants, including a novel c.2833G>A variant associated with early-onset cone-rod dystrophy. We highlight the severity and rapid progression of the disease and offer ABEs as a potential future therapeutic approach for this devastating blinding condition.
Many paths lead to immunology.
While some people pore over the textbook and train through the classics of the field, many scientists come to immunology when they discover it intersecting with their "first love" interests. Five of these "accidental immunologists" tell us how they found their way to a fascination with the immune system.
Hierarchical syntax model of music predicts theta power during music listening.
Linguistic research showed that the depth of syntactic embedding is reflected in brain theta power. Here, we test whether this also extends to non-linguistic stimuli, specifically music. We used a hierarchical model of musical syntax to continuously quantify two types of expert-annotated harmonic dependencies throughout a piece of Western classical music: prolongation and preparation. Prolongations can roughly be understood as a musical analogue to linguistic coordination between constituents that share the same function (e.g., 'pizza' and 'pasta' in 'I ate pizza and pasta'). Preparation refers to the dependency between two harmonies whereby the first implies a resolution towards the second (e.g., dominant towards tonic; similar to how the adjective implies the presence of a noun in 'I like spicy … '). Source reconstructed MEG data of sixty-five participants listening to the musical piece was then analysed. We used Bayesian Mixed Effects models to predict theta envelope in the brain, using the number of open prolongation and preparation dependencies as predictors whilst controlling for audio envelope. We observed that prolongation and preparation both carry independent and distinguishable predictive value for theta band fluctuation in key linguistic areas such as the Angular, Superior Temporal, and Heschl's Gyri, or their right-lateralised homologues, with preparation showing additional predictive value for areas associated with the reward system and prediction. Musical expertise further mediated these effects in language-related brain areas. Results show that predictions of precisely formalised music-theoretical models are reflected in the brain activity of listeners which furthers our understanding of the perception and cognition of musical structure.
Definition of Implanted Neurological Device Abandonment: A Systematic Review and Consensus Statement.
IMPORTANCE: Establishing a formal definition for neurological device abandonment has the potential to reduce or to prevent the occurrence of this abandonment. OBJECTIVE: To perform a systematic review of the literature and develop an expert consensus definition for neurological device abandonment. EVIDENCE REVIEW: After a Royal Society Summit on Neural Interfaces (September 13-14, 2023), a systematic English language review using PubMed was undertaken to investigate extant definitions of neurological device abandonment. Articles were reviewed for relevance to neurological device abandonment in the setting of deep brain, vagal nerve, and spinal cord stimulation. This review was followed by the convening of an expert consensus group of physicians, scientists, ethicists, and stakeholders. The group summarized findings, added subject matter experience, and applied relevant ethics concepts to propose a current operational definition of neurological device abandonment. Data collection, study, and consensus development were done between September 13, 2023, and February 1, 2024. FINDINGS: The PubMed search revealed 734 total articles, and after review, 7 articles were found to address neurological device abandonment. The expert consensus group addressed findings as germane to neurological device abandonment and added personal experience and additional relevant peer-reviewed articles, addressed stakeholders' respective responsibilities, and operationally defined abandonment in the context of implantable neurotechnological devices. The group further addressed whether clinical trial failure or shelving of devices would constitute or be associated with abandonment as defined. Referential to these domains and dimensions, the group proposed a standardized definition for abandonment of active implantable neurotechnological devices. CONCLUSIONS AND RELEVANCE: This study's consensus statement suggests that the definition for neurological device abandonment should entail failure to provide fundamental aspects of patient consent; fulfill reasonable responsibility for medical, technical, or financial support prior to the end of the device's labeled lifetime; and address any or all immediate needs that may result in safety concerns or device ineffectiveness and that the definition of abandonment associated with the failure of a research trial should be contingent on specific circumstances.
A comprehensive analysis of APOE genotype effects on human brain structure in the UK Biobank.
Alzheimer's disease (AD) risk is increased in carriers of the apolipoprotein E (APOE) ε4 allele and decreased in ε2 allele carriers compared with the ε3ε3 genotype. The aim of this study was to determine whether: the APOE genotype affects brain grey (GM) or white matter (WM) structure; and if differences exist, the age when they become apparent and whether there are differential effects by sex. We used cross-sectional magnetic resonance imaging data from ~43,000 (28,494 after pre-processing) white British cognitively healthy participants (7,446 APOE ε4 carriers) aged 45-80 years from the UK Biobank cohort and investigated image-derived phenotypes (IDPs). We observed no statistically significant effects of APOE genotype on GM structure volumes or median T2* in subcortical structures, a measure related to iron content. The volume of white matter hyperintensities differed significantly between APOE genotype groups with higher volumes in APOE ε4ε4 (effect size 0.14 standard deviations [SD]) and ε3ε4 carriers (effect size 0.04 SD) but no differences in ε2 carriers compared with ε3ε3 carriers. WM integrity measures in the dorsal (mean diffusivity [MD]) and ventral cingulum (MD and intracellular volume fraction), posterior thalamic radiation (MD and isotropic volume fraction) and sagittal stratum (MD) indicated lower integrity in APOE ε4ε4 carriers (effect sizes around 0.2-0.3 SD) and ε3ε4 (effect sizes around 0.05 SD) carriers but no differences in ε2 carriers compared with the APOE ε3ε3 genotype. Effects did not differ between men and women. APOE ε4 homozygotes had lower WM integrity specifically at older ages with a steeper decline of WM integrity from the age of 60 that corresponds to around 5 years greater "brain age". APOE genotype affects various white matters measures, which might be indicative of preclinical AD processes. This hypothesis can be assessed in future when clinical outcomes become available.
Restless legs symptoms increased during COVID-19 pandemic. International ICOSS-survey.
BACKGROUND AND OBJECTIVES: Restless legs syndrome (RLS) has been associated with anxiety, depression, insomnia, lifestyle factors and infections. We aimed to study the prevalence of symptoms of RLS during the COVID-19 pandemic versus pre-pandemic. We hypothesized that pre-existing RLS symptoms worsened and pandemic-related factors may have triggered new symptoms of RLS. METHODS: Adults (≥18 years) from fifteen countries across four continents participated in an online survey between May and August 2020. The harmonized questionnaire included a validated single question on RLS with response alternatives from 1 to 5 on a scale from never to every/almost every evening or night. Other measures were the Insomnia Severity Index (ISI), measures of symptoms of anxiety (GAD-2) and depression (PHQ-2), and questions on different pandemic-related factors. RESULTS: Altogether, 17 846 subjects (63.8 % women) were included in the final analyses. The mean age was 41.4 years (SD 16.1). During the pandemic, symptoms of RLS (≥3 evenings/nights per week) were more common 9.1 % (95 % CI 8.7-10.1) compared to 5.4 % (95 % CI 4.9-6.0) before the pandemic (P
PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation.
PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways.