Disruption of Mitochondrial DNA Replication in Drosophila Increases Mitochondrial Fast Axonal Transport In Vivo

Mutations in mitochondrial DNA polymerase (pol γ) cause several progressive human diseases including Parkinson's disease, Alper's syndrome, and progressive external ophthalmoplegia. At the cellular level, disruption of pol γ leads to depletion of mtDNA, disrupts the mitochondrial respiratory chain, and increases susceptibility to oxidative stress. Although recent studies have intensified focus on the role of mtDNA in neuronal diseases, the changes that take place in mitochondrial biogenesis and mitochondrial axonal transport when mtDNA replication is disrupted are unknown. Using high-speed confocal microscopy, electron microscopy and biochemical approaches, we report that mutations in pol γ deplete mtDNA levels and lead to an increase in mitochondrial density in Drosophila proximal nerves and muscles, without a noticeable increase in mitochondrial fragmentation. Furthermore, there is a rise in flux of bidirectional mitochondrial axonal transport, albeit with slower kinesin-based anterograde transport. In contrast, flux of synaptic vesicle precursors was modestly decreased in pol γ−α mutants. Our data indicate that disruption of mtDNA replication does not hinder mitochondrial biogenesis, increases mitochondrial axonal transport, and raises the question of whether high levels of circulating mtDNA-deficient mitochondria are beneficial or deleterious in mtDNA diseases

Management of bradyarrhythmias in heart failure: A tailored approach

Patients with heart failure (HF) may develop a range of bradyarrhythmias including sinus node dysfunction, various degrees of atrioventricular block, and ventricular conduction delay. Device implantation has been recommended in these patients, but the specific etiology should be sought as it may influence the choice of the type of device required (pacemaker vs. implantable cardiac defibrillator). Also, pacing mode must be carefully set in patients with heart failure (HF) and left ventricular systolic dysfunction.In this chapter, we summarize the knowledge required for a tailored approach to bradyarrhythmias in patients with heart failure

Career intentions of medical students in the UK: a national, cross-sectional study (AIMS study)

Objective To determine current UK medical students’ career intentions after graduation and on completing the Foundation Programme (FP), and to ascertain the motivations behind these intentions.Design Cross-sectional, mixed-methods survey of UK medical students, using a non-random sampling method.Setting All 44 UK medical schools recognised by the General Medical Council.Participants All UK medical students were eligible to participate. The study sample consisted of 10 486 participants, approximately 25.50% of the medical student population.Outcome measures Career intentions of medical students postgraduation and post-FP, motivations behind these career intentions, characterising the medical student population and correlating demographic factors and propensity to leave the National Health Service (NHS).Results The majority of participating students (8806/10 486, 83.98%) planned to complete both years of the FP after graduation, with under half of these students (4294/8806, 48.76%) intending to pursue specialty training thereafter. A subanalysis of career intentions after the FP by year of study revealed a significant decrease in students’ intentions to enter specialty training as they advanced through medical school. Approximately a third of surveyed students (3392/10 486, 32.35%) intended to emigrate to practise medicine, with 42.57% (n=1444) of those students not planning to return. In total, 2.89% of students intended to leave medicine altogether (n=303). Remuneration, work-life balance and working conditions were identified as important factors in decision-making regarding emigration and leaving the profession. Subgroup analyses based on gender, type of schooling, fee type and educational background were performed. Only 17.26% of surveyed students were satisfied or very satisfied with the overall prospect of working in the NHS.Conclusions The Ascertaining the career Intentions of UK Medical Students study highlights UK students’ views and career intentions, revealing a concerning proportion of those surveyed considering alternative careers or emigration. Addressing factors such as remuneration, work-life balance and working conditions may increase retention of doctors and improve workforce planning efforts

The role of medical schools in UK students’ career intentions: findings from the AIMS study

Abstract Objectives To investigate differences in students’ career intentions between UK medical schools. Design Cross-sectional, mixed-methods online survey. Setting The primary study included all 44 UK medical schools, with this analysis comprising 42 medical schools. Participants Ten thousand four hundred eighty-six UK medical students. Main outcome measures Career intentions of medical students, focusing on differences between medical schools. Secondary outcomes included variation in medical students’ satisfaction with a prospective career in the NHS, by medical school. Results 2.89% of students intended to leave medicine altogether, with Cambridge Medical School having the highest proportion of such respondents. 32.35% of respondents planned to emigrate for practice, with Ulster medical students being the most likely. Of those intending to emigrate, the University of Central Lancashire saw the highest proportion stating no intentions to return. Cardiff Medical School had the greatest percentage of students intending to assume non-training clinical posts after completing FY2. 35.23% of participating medical students intended to leave the NHS within 2 years of graduating, with Brighton and Sussex holding the highest proportion of these respondents. Only 17.26% were satisfied with the prospect of working in the NHS, with considerable variation nationally; Barts and the London medical students had the highest rates of dissatisfaction. Conclusions This study reveals variability in students’ career sentiment across UK medical schools, emphasising the need for attention to factors influencing these trends. A concerning proportion of students intend to exit the NHS within 2 years of graduating, with substantial variation between institutions. Students’ intentions may be shaped by various factors, including curriculum focus and recruitment practices. It is imperative to re-evaluate these aspects within medical schools, whilst considering the wider national context, to improve student perceptions towards an NHS career. Future research should target underlying causes for these disparities to facilitate improvements to career satisfaction and retention. </jats:sec