A Genome-wide Screen Reveals that Reducing Mitochondrial DNA Polymerase Can Promote Elimination of Deleterious Mitochondrial Mutations.

A mutant mitochondrial genome arising amid the pool of mitochondrial genomes within a cell must compete with existing genomes to survive to the next generation. Even weak selective forces can bias transmission of one genome over another to affect the inheritance of mitochondrial diseases and guide the evolution of mitochondrial DNA (mtDNA). Studies in several systems suggested that purifying selection in the female germline reduces transmission of detrimental mitochondrial mutations [1-7]. In contrast, some selfish genomes can take over despite a cost to host fitness [8-13]. Within individuals, the outcome of competition is therefore influenced by multiple selective forces. The nuclear genome, which encodes most proteins within mitochondria, and all external regulators of mitochondrial biogenesis and dynamics can influence the competition between mitochondrial genomes [14-18], yet little is known about how this works. Previously, we established a Drosophila line transmitting two mitochondrial genomes in a stable ratio enforced by purifying selection benefiting one genome and a selfish advantage favoring the other [8]. Here, to find nuclear genes that impact mtDNA competition, we screened heterozygous deletions tiling ∼70% of the euchromatic regions and examined their influence on this ratio. This genome-wide screen detected many nuclear modifiers of this ratio and identified one as the catalytic subunit of mtDNA polymerase gene (POLG), tam. A reduced dose of tam drove elimination of defective mitochondrial genomes. This study suggests that our approach will uncover targets for interventions that would block propagation of pathogenic mitochondrial mutations

Health economics in a world of uneconomic growth

Multiple, accelerating and interacting ecological crises are increasingly understood as constituting a major threat to human health and well-being. Unconstrained economic growth is strongly implicated in these growing crises, and it has been argued that this growth has now become "uneconomic growth", which is a situation where the size of the economy is still expanding, but this expansion is causing more harm than benefit. This article summarises the multiple pathways by which uneconomic growth can be expected to harm human health. It describes how health care systems-especially through overuse, low value and poor quality care-can themselves drive uneconomic growth. Health economists need to understand not only the consequences of environmental impacts on health care, but also the significance of uneconomic growth, and pay closer attention to the growing body of work by heterodox economists, especially in the fields of ecological and feminist economics. This will involve paying closer heed to the existence and consequences of diminishing marginal returns to health care consumption at high levels; the central importance of inequalities and injustice in health; and the need to remedy health economists' currently limited ability to deal effectively with low value care, overdiagnosis and overtreatment

Two-year real-world outcome data from a single tertiary centre shows reduced ustekinumab persistence in a non-bio-naïve Crohn's disease cohort with penetrating disease, -ostomies and sarcopenia

BACKGROUND: Ustekinumab was approved in 2016 for the treatment of moderate-severe Crohn's disease (CD). Clinical trials and real-world studies have suggested ustekinumab to be a safe and effective treatment; however, studies to date infrequently use imaging techniques to predict response to biologics in CD. OBJECTIVES: We assessed the 2-year real-world effectiveness and safety of ustekinumab in a tertiary CD cohort with the use of novel imaging techniques. DESIGN: Retrospective cohort study. METHODS: Retrospective data were collected between 2016 and 2021. Study end points included ustekinumab persistence, biological and/or clinical response and remission at 12, 18 and 24 months. Statistical analysis included demographic and inferential analyses. RESULTS: In all, 131 CD patients [57.3% female, median age of 26.0 (21.0-37.0)] were included. Patients were non-bio naïve, and the majority received ustekinumab as third- or fourth-line treatment. At 24 months, 61.0% (80/131) persisted with ustekinumab [52.7% (69/131) steroid free]. Clinical response was reported in 55.2% (37/67), clinical remission in 85.7% (57/67), biological response in 46.8% (22/47) and biological remission in 31.9% (15/47) of patients at 24 months. The low outcome numbers were attributable to missing data. Improvements in routine disease markers, including C-reactive protein and Harvey-Bradshaw Index, were also reflected in magnetic resonance imaging-derived disease scores. The presence of penetrating CD, an -ostomy and sarcopenia were all predictors of poorer ustekinumab outcomes (p < 0.05). CONCLUSION: Ustekinumab is effective in non-bio-naïve CD patients with non-stricturing, non-penetrating disease with an unremarkable safety profile but may be less effective in those with penetrating disease, -ostomies and sarcopenia

Blood-based epigenome-wide analyses of cognitive abilities

BACKGROUND: Blood-based markers of cognitive functioning might provide an accessible way to track neurodegeneration years prior to clinical manifestation of cognitive impairment and dementia. RESULTS: Using blood-based epigenome-wide analyses of general cognitive function, we show that individual differences in DNA methylation (DNAm) explain 35.0% of the variance in general cognitive function (g). A DNAm predictor explains ~4% of the variance, independently of a polygenic score, in two external cohorts. It also associates with circulating levels of neurology- and inflammation-related proteins, global brain imaging metrics, and regional cortical volumes. CONCLUSIONS: As sample sizes increase, the ability to assess cognitive function from DNAm data may be informative in settings where cognitive testing is unreliable or unavailable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13059-021-02596-5

Antipsychotic medication versus psychological intervention versus a combination of both in adolescents with first-episode psychosis (MAPS): a multicentre, three-arm, randomised controlled pilot and feasibility study

Background Evidence for the effectiveness of treatments in early-onset psychosis is sparse. Current guidance for the treatment of early-onset psychosis is mostly extrapolated from trials in adult populations. The UK National Institute for Health and Care Excellence has recommended evaluation of the clinical effectiveness and cost-effectiveness of antipsychotic drugs versus psychological intervention (cognitive behavioural therapy [CBT] and family intervention) versus the combination of these treatments for early-onset psychosis. The aim of this study was to establish the feasibility of a randomised controlled trial of antipsychotic monotherapy, psychological intervention monotherapy, and antipsychotics plus psychological intervention in adolescents with first-episode psychosis. Methods We did a multicentre pilot and feasibility trial according to a randomised, single-blind, three-arm, controlled design. We recruited participants from seven UK National Health Service Trust sites. Participants were aged 14–18 years; help-seeking; had presented with first-episode psychosis in the past year; were under the care of a psychiatrist; were showing current psychotic symptoms; and met ICD-10 criteria for schizophrenia, schizoaffective disorder, or delusional disorder, or met the entry criteria for an early intervention for psychosis service. Participants were assigned (1:1:1) to antipsychotics, psychological intervention (CBT with optional family intervention), or antipsychotics plus psychological intervention. Randomisation was via a web-based randomisation system, with permuted blocks of random size, stratified by centre and family contact. CBT incorporated up to 26 sessions over 6 months plus up to four booster sessions, and family intervention incorporated up to six sessions over 6 months. Choice and dose of antipsychotic were at the discretion of the treating consultant psychiatrist. Participants were followed up for a maximum of 12 months. The primary outcome was feasibility (ie, data on trial referral and recruitment, session attendance or medication adherence, retention, and treatment acceptability) and the proposed primary efficacy outcome was total score on the Positive and Negative Syndrome Scale (PANSS) at 6 months. Primary outcomes were analysed by intention to treat. Safety outcomes were reported according to as-treated status, for all patients who had received at least one session of CBT or family intervention, or at least one dose of antipsychotics. The study was prospectively registered with ISRCTN, ISRCTN80567433. Findings Of 101 patients referred to the study, 61 patients (mean age 16·3 years [SD 1·3]) were recruited from April 10, 2017, to Oct 31, 2018, 18 of whom were randomly assigned to psychological intervention, 22 to antipsychotics, and 21 to antipsychotics plus psychological intervention. The trial recruitment rate was 68% of our target sample size of 90 participants. The study had a low referral to recruitment ratio (around 2:1), a high rate of retention (51 [84%] participants retained at the 6-month primary endpoint), a high rate of adherence to psychological intervention (defined as six or more sessions of CBT; in 32 [82%] of 39 participants in the monotherapy and combined groups), and a moderate rate of adherence to antipsychotic medication (defined as at least 6 consecutive weeks of exposure to antipsychotics; in 28 [65%] of 43 participants in the monotherapy and combined groups). Mean scores for PANSS total at the 6-month primary endpoint were 68·6 (SD 17·3) for antipsychotic monotherapy (6·2 points lower than at randomisation), 59·8 (13·7) for psychological intervention (13·1 points lower than at randomisation), and 62·0 (15·9) for antipsychotics plus psychological intervention (13·9 points lower than at randomisation). A good clinical response at 6 months (defined as ≥50% improvement in PANSS total score) was achieved in four (22%) of 18 patients receiving antipsychotic monotherapy, five (31%) of 16 receiving psychological intervention, and five (29%) of 17 receiving antipsychotics plus psychological intervention. In as-treated groups, serious adverse events occurred in eight [35%] of 23 patients in the combined group, two [13%] of 15 in the antipsychotics group, four [24%] of 17 in the psychological intervention group, and four [80%] of five who did not receive any treatment. No serious adverse events were considered to be related to participation in the trial. Interpretation This trial is the first to show that a head-to-head clinical trial comparing psychological intervention, antipsychotics, and their combination is safe in young people with first-episode psychosis. However, the feasibility of a larger trial is unclear because of site-specific recruitment challenges, and amendments to trial design would be needed for an adequately powered clinical and cost-effectiveness trial that provides robust evidence

Health, education, and social care provision after diagnosis of childhood visual disability

Aim: To investigate the health, education, and social care provision for children newly diagnosed with visual disability.Method: This was a national prospective study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), ascertaining new diagnoses of visual impairment or severe visual impairment and blindness (SVIBL), or equivalent vi-sion. Data collection was performed by managing clinicians up to 1-year follow-up, and included health and developmental needs, and health, education, and social care provision.Results: BCVIS2 identified 784 children newly diagnosed with visual impairment/SVIBL (313 with visual impairment, 471 with SVIBL). Most children had associated systemic disorders (559 [71%], 167 [54%] with visual impairment, and 392 [84%] with SVIBL). Care from multidisciplinary teams was provided for 549 children (70%). Two-thirds (515) had not received an Education, Health, and Care Plan (EHCP). Fewer children with visual impairment had seen a specialist teacher (SVIBL 35%, visual impairment 28%, χ2p < 0.001), or had an EHCP (11% vs 7%, χ2p < 0 . 01).Interpretation: Families need additional support from managing clinicians to access recommended complex interventions such as the use of multidisciplinary teams and educational support. This need is pressing, as the population of children with visual impairment/SVIBL is expected to grow in size and complexity.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited

A three-arm feasibility randomised controlled trial comparing antipsychotic medication to psychological intervention to a combined treatment in adolescents with first episode psychosis: The Managing Adolescent first episode Psychosis Study (MAPS)

Background: The evidence base for treatments for early-onset psychosis (EOP) is limited and of low quality. Current guidance for the treatment of EOP is mostly extrapolated from trials in adult populations. NICE, in the United Kingdom (UK), make a specific research recommendation for the evaluation of clinical and cost-effectiveness of antipsychotics (AP), versus psychological intervention (cognitive behaviour therapy [CBT] and family intervention), versus combination treatment for EOP. The National Institute for Health Research (NIHR) in the UK commissioned this research to establish feasibility and acceptability of a definitive trial examining these three treatment options. Methods: We conducted a multi-site, Prospective Randomised Open Blinded Evaluation (PROBE) design, feasibility randomised controlled trial (RCT) comparing AP monotherapy with psychological intervention monotherapy (PI) plus a combination of these treatments in 14-18-year olds with a first episode of psychosis. We recruited participants from seven United Kingdom sites. Participants were followed-up at six and 12 months. Cognitive behavioural therapy incorporated up to 26 sessions over 6 months plus up to four booster sessions. Family intervention included up to six sessions over 6 months. Choice and dose of antipsychotic were at the discretion of the treating consultant psychiatrist. The primary outcome was feasibility data (recruitment, retention, acceptability) and the main effectiveness outcome was the Positive and Negative Syndrome Scale (PANSS) total score at 6 months. We conducted a repeated-measures analysis of the proposed primary outcome (PANSS) and the secondary outcome, the Questionnaire about the Process of Recovery (QPR) using a mixed effects model to account for the discrete timing of the follow-up assessments and adjusted for site. Safety outcomes were reported on the basis of as treated status defined as any one session of CBT or any one dose of APs; descriptive statistics are reported for safety outcomes. The study was prospectively registered on 27th February 2017, http://www.isrctn.com/ISRCTN80567433. Findings: 61 patients (aged 14-18 years; mean 16.3, SD 1.3) were recruited from 1st April 2017 to 31st October 2018, 18 were assigned to psychological intervention, 22 to antipsychotics and 21 to the combination. The feasibility of recruitment was unclear, since the trial only recruited 61 of a target of 90 participants. The study had a low referral: randomisation ratio (101:61), high rates of retention (>80%), high rates of adherence for psychological intervention (82.1%) defined as 6 or more sessions of CBT, and moderate rates of adherence for antipsychotic medication (65.1%), defined as 6 or more consecutive weeks of APs. The median number of sessions for CBT for those in the PI arm was 14 (IQR 9, 23) and 15 in the combined arm (IQR 9, 17). Of those in receipt of APs the mean duration that the participant remained on the medication was 31.5 weeks (SD 14.6, minimum 8.7 and maximum 52). There were no serious adverse events considered to be related to the trial. Interpretation: This is the first trial to show that it is safe to conduct a head-to-head clinical trial comparing psychological intervention with antipsychotics and the combination in people in young people with a first-episode psychosis. However, feasibility is unclear due to not meeting the recruitment progression criteria, so amendments to trial design are required in order to conduct an adequately powered clinical and cost effectiveness trial to provide robust evidence

Investigating the Regulation of Mitochondrial DNA Dynamics with a Drosophila Model

The maternally inherited mitochondrial DNA (mtDNA) is a multi-copy genome that encodes several mitochondrial proteins essential for energy production. Heteroplasmy, the state of possessing multiple variants of mtDNA, is very common in humans. The levels of these mtDNA variants are subject to genetic drift and selection during development and ageing. Disease symptoms will manifest when a detrimental mtDNA variant reaches a high level. To date, over 350 pathogenic mtDNA mutations have been identified as causing mtDNA-associated diseases, for which there are no cures. Given the role that mtDNA plays in disease, there is an increasing pressure to better understand the mechanisms underlying mtDNA selection. Previous studies of heteroplasmy dynamics during development have demonstrated tissue-specificity and age-dependence, but no clear mechanistic explanation has emerged, mainly due to a lack of animal models for systematic and gene-focused studies. Here, I developed a cell culture-based system for investigating mtDNA selection, based on a Drosophila melanogaster line that transmits a temperature-sensitive mtDNA variant alongside a functional mtDNA variant at a stable ratio. I generated multiple cell lines from embryos of the heteroplasmic flies and showed that they could maintain a balance of the two mtDNA variants which I could manipulate. The established heteroplasmic cell lines allowed me to perform high-throughput RNAi and compound screens to identify factors that affect the heteroplasmic ratio. By doing so, I demonstrated that the knockdown of a number of genes and the application of certain small molecules changed the heteroplasmic ratio over a few cell divisions. In particular, I revealed that RNAi-mediated knockdown of Regulatory particle triple-A ATPase 2 or Regulatory particle non-ATPase 11, two conserved components of the proteasome, was sufficient to increase the proportion of detrimental mtDNA. This indicated that 26S proteasome activity is involved in maintaining functional mtDNA levels and has important implications for neurodegenerative diseases, which are often associated with proteasome impairment. In this work, I also investigated mtDNA selection at the organismal level. A deficiency screen using the stable heteroplasmic fly line identified genes such as mtDNA polymerase PolG1 that influence the ratio of mtDNA variants over generations, providing an understanding of germline selection acting at the mitochondrion level mediated by PolG1 availability. I explored the role of individual genes in selective transmission of mtDNA by employing CRISPR/Cas9-mediated mutagenesis and found that whilst PolG1 can influence the ratio, there is no evidence that mtDNA replisome components PolG2 or mtDNA-helicase do so. Taken together, my work demonstrates that the nuclear genome plays a complex role in determining the outcome of mtDNA selection in cultured cells as well as in vivo. Furthermore, the small molecules I identified have the potential to be developed into novel therapeutic methods for lowering the level of detrimental mtDNA in patients. mtDNA selection within our bodies is not an inscrutability: it can be modelled in flies and, hopefully, soon manipulated in patients