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Cells are equipped with intracellular RIG-like Receptors (RLRs) detecting double stranded (ds)RNA, a molecule with Pathogen-Associated Molecular Pattern (PAMPs) generated during the life cycle of many viruses. Melanoma Differentiation-Associated protein 5 (MDA5), a helicase enzyme member of the RLRs encoded by the ifih1 gene, binds to long dsRNA molecules during a viral infection and initiates production of type I interferon (IFN1) which orchestrates the antiviral response. In order to understand the contribution of MDA5 to viral resistance in fish cells, we have isolated a clonal Chinook salmon Oncorhynchus tshawytscha epithelial-like cell line invalidated for the ifih1 gene by CRISPR/Cas9 genome editing. We demonstrated that IFN1 induction is impaired in this cell line after infection with the Snakehead Rhabdovirus (SHRV), the Salmon Alphavirus (SAV) or Nervous Necrosis Virus (NNV). The cell line, however, did not show any increase in cytopathic effect when infected with SHRV or SAV. Similarly, no cytopathic effect was observed in the ifih1-/- cell line when infected with Infectious Pancreatic Necrosis Virus (IPNV), Infectious Haemorrhagic Necrotic Virus (IHNV). These results indicate the redundancy of the antiviral innate defence system in CHSE-derived cells, which helps with circumventing viral evasion strategies.
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Helicase IFIH1 Induzida por Interferon , Salmão , Animais , Salmão/virologia , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/metabolismo , Linhagem Celular , Sistemas CRISPR-Cas , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Interferon Tipo I/metabolismo , Doenças dos Peixes/virologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/genéticaRESUMO
Bacteremia can be life-threatening, and highly medicalized patients, such as those with complex congenital heart disease, are at high risk. Infectious diseases (ID) consultation is associated with improved outcomes in bacteremia. We noted an opportunity for improvement in management of positive blood cultures in our cardiac care unit (CCU). We completed a quality improvement project that included a single plan-do-study-act cycle consisting of a policy of routine ID consultation for all positive blood cultures events in the CCU. Our outcome measure of interest was percentage of appropriately managed blood culture events, the process measure was percentage of blood culture events for which the ID service was formally consulted, and the balancing measure was number of individual patients for whom the ID service was formally consulted. Appropriate antimicrobial management was determined via chart review by an ID physician. Data were analyzed via run chart and simple statistics. Following the intervention, the rate of appropriately managed positive blood culture events increased from a baseline of 86% to 98%, and the rate of ID consultation for these events increased from 75% to 98%. A shift was noted in run charts for both the outcome and process measures. There was an increase in patients for whom the ID service was consulted throughout the entire study period. We successfully implemented mandatory ID consultations in a CCU to increase proportion of appropriately managed blood cultures. While this intervention cannot be universally applied, others may find it useful in selected scenarios.
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Late-onset Pompe Disease (LOPD) is a rare genetic disorder caused by the deficiency of acid alpha-glucosidase leading to progressive cellular dysfunction due to the accumulation of glycogen in the lysosome. The mechanism of relentless muscle damage - a classic manifestation of the disease - has been extensively studied by analysing the whole muscle tissue; however, little, if any, is known about transcriptional heterogeneity among nuclei within the multinucleated skeletal muscle cells. This is the first report of application of single nuclei RNA sequencing to uncover changes in the gene expression profile in muscle biopsies from eight patients with LOPD and four muscle samples from age and gender matched healthy controls. We matched these changes with histology findings using GeoMx Spatial Transcriptomics to compare the transcriptome of control myofibers from healthy individuals with non-vacuolated (histologically unaffected) and vacuolated (histologically affected) myofibers of LODP patients. We observed an increase in the proportion of slow and regenerative muscle fibers and macrophages in LOPD muscles. The expression of the genes involved in glycolysis was reduced, whereas the expression of the genes involved in the metabolism of lipids and amino acids was increased in non-vacuolated fibers, indicating early metabolic abnormalities. Additionally, we detected upregulation of autophagy genes, and downregulation of the genes involved in ribosomal and mitochondrial function leading to defective oxidative phosphorylation. The upregulation of the genes associated with inflammation, apoptosis and muscle regeneration was observed only in vacuolated fibers. Notably, enzyme replacement therapy - the only available therapy for the disease - showed a tendency to restore metabolism dysregulation, particularly within slow fibers. A combination of single nuclei RNA sequencing and spatial transcriptomics revealed the landscape of normal and the diseased muscle, and highlighted the early abnormalities associated with the disease progression. Thus, the application of these two new cutting-edge technologies provided insight into the molecular pathophysiology of muscle damage in LOPD and identified potential avenues for therapeutic intervention.
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PROBLEM: Little is known about the maternity experiences of women who have been trafficked and further investigation is needed to better inform midwifery practice and to ensure that the voices of women are heard when developing guidance. BACKGROUND: People who have been trafficked experience a range of health problems that could impact on pregnancy. AIM: The aim of this study was to explore the experiences of pregnancy and NHS maternity care for women who have been trafficked, as well as increasing understanding of social and health factors that may impact on pregnancy outcomes. METHODS: A qualitative interview study was conducted. Participants (professionals and service users) were recruited using purposive sampling. Data were analysed using thematic analysis. FINDINGS: Seventeen interviews were conducted (5 service users and 12 professionals). Five themes were identified: 'One Size Fits All', 'Loss of Control', 'Social Complexity', 'Bridging Gaps', and 'Emotional Load'. DISCUSSION: Our findings identify that women are expected to fit into a standardised model of maternity care that does not always recognise their complex individual physical, emotional or social needs, or provide them with control. Support workers play a vital role in helping women navigate and make sense of their maternity care. CONCLUSION: Despite the issues identified, our research highlighted the positive impact of individualised care, particularly when women received continuity of care. A joined-up, trauma-informed approach between midwives and support workers could help improve care for women who have been trafficked.
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Serviços de Saúde Materna , Pesquisa Qualitativa , Medicina Estatal , Humanos , Feminino , Gravidez , Adulto , Medicina Estatal/organização & administração , Serviços de Saúde Materna/normas , Gestantes/psicologia , Reino UnidoRESUMO
The simple body plan and semitranslucent cuticle of the Drosophila larva allow for imaging of structures close to the body wall within intact animals. These include sensory neurons, muscles, neuromuscular junctions, and some regions of the segmental nerve. However, imaging within an intact larva requires a strategy to immobilize the animal in a position that presents the structures within the working distance of the microscope objective. Although various methods have been implemented for Drosophila larvae, this protocol describes a simple and noninvasive method that makes use of the polydimethylsiloxane (PDMS) larva chip. This larva chip immobilizes animals without the use of anesthetics or changes in temperature, which alter neuronal physiology, making it suitable for calcium imaging of endogenous activity in live animals. The membrane is air-permeable. Animals robustly survive short periods of immobilization (up to 30 min) and can even survive longer time periods. Since animals recover well after the procedure, the same animal can be reimaged multiple times. This makes the method amenable to manipulations such as laser microsurgery, photobleaching, and photoconversion followed by imaging of outcomes of these manipulations over time.
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A fundamental feature of nervous systems is a highly specified synaptic connectivity between cells and the ability to adaptively change this connectivity through plasticity mechanisms. Plasticity mechanisms are highly relevant for responding to nervous system damage, and studies using nervous system injury paradigms in Drosophila (as well as other model organisms) have revealed conserved molecular pathways that are triggered by axon damage. Simple assays that introduce injuries to axons in either adult flies or larvae have proven to be particularly powerful for uncovering mechanisms of axonal degeneration and clearance. They have also been used to reveal requirements for regrowth of axons and dendrites, as well as signaling pathways that regulate cellular responses to nerve injury. Here we review commonly used and simple to carry out techniques that enable experimenters to study responses to axonal damage in either adult flies (following antennal transection) or larvae (following nerve crush to segmental nerves). Because axons and dendrites in the larval peripheral nervous system can be readily visualized through the translucent cuticle, another versatile method to probe injury responses is to focus high-energy laser light to a small and specific location in the animal. We therefore discuss a method for immobilizing intact larvae for imaging through the cuticle to carry out injury by pulse dye laser, which can be used to generate many different kinds of injuries and directed ablations within intact larvae. These techniques, combined with powerful genetic tools in Drosophila, make the fruit fly an excellent model system for studying the effects of injury and the mechanisms of axon degeneration, synapse plasticity, and immune response.
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The long length of axons makes them vulnerable to damage; hence, it is logical that nervous systems have evolved adaptive mechanisms for responding to axon damage. Studies in Drosophila melanogaster have identified evolutionarily conserved molecular pathways that enable axonal degeneration and regeneration of damaged axons and/or dendrites. This protocol describes a simple method for inducing nerve crush injury to motoneuron and sensory neuron axons in the peripheral (segmental) nerves in second- or early third-instar larvae. Small forceps are used to pinch the cuticle at a location that overlays the segmental nerves. Although the connective tissue of the nerves remains intact and the larva survives the injury, single motoneuron and sensory neuron axons incur a break in continuity at the damage site and then undergo Wallerian degeneration distal to the break. This degeneration includes the dismantling of neuromuscular junction (NMJ) synapses formed by the axons that incurred damage. With stereotyped anatomy and accessibility to structural and electrophysiological studies, the larval NMJ is a good model to characterize the cellular changes that occur in synapses undergoing degeneration and to identify conditions that can protect axons and synapses from degeneration.
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Neurons extend their axons and dendrites over long distances and rely on evolutionarily conserved mechanisms to maintain the cellular structure and function of neurites at a distance from their cell body. Neurites that lose connection with their cell body following damage or stressors to their cytoskeleton undergo a programmed self-destruction process akin to apoptosis but using different cellular machinery, termed Wallerian degeneration. While first described for vertebrate axons by Augustus Waller in 1850, key discoveries of the enzymes that regulate Wallerian degeneration were made through forward genetic screens in Drosophila melanogaster Powerful techniques for genetic manipulation and visualization of single neurons combined with simple methods for introducing axotomy (neuron severing) to certain neuron types in Drosophila have enabled the discovery and study of the cellular machinery responsible for Wallerian degeneration, in addition to mechanisms that enable clearance of the resulting debris. This protocol describes how to study the degeneration and clearance of axons from olfactory receptor neurons (ORNs). These peripheral neurons reside in the antennae and project axons to olfactory glomeruli of the anterior brain. Simple and nonlethal removal of antennae from adult flies causes axotomy of ORNs, and the fate of the injured axons can be readily visualized in a whole-mount dissected brain. This assay takes advantage of well-characterized genetic methods to robustly and specifically label subsets of ORNs. This method of neurite labeling and axotomy was the first axon injury paradigm to be developed in flies and is still regularly used due to its simplicity to perform, dissect, image, and analyze.
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Laser microsurgery is a robust method to ablate specific cells in the nervous system and probe the functional consequences of their loss in the animal. By introducing focal lesions to small locations in the animal, laser microsurgery also enables disruptions of specific connections within neuronal circuits and the study of how the nervous system responds to precise forms of damage (for instance, damage to specific axons or dendrites, which have been found to evoke different kinds of responses in neurons). The MicroPoint laser is a pulsed dye laser that can be mounted onto any standard microscope, hence is an affordable alternative to two-photon lasers for providing high powered focal ablations. This protocol describes how to use a MicroPoint laser ablation system to induce focal injuries in Drosophila larvae. This protocol guides a user who has access to a MicroPoint laser that has already been installed onto an appropriate microscope for high-resolution imaging and configured for laser ablation using Coumarin 440 dye. The protocol covers how to use the laser to carry out surgeries or ablation, how to change the laser dye and calibrate the power settings, and how to make sure the laser is properly focused. While the protocol provides an example of axotomy (axon severing) in the peripheral nervous system of Drosophila larvae, use of the MicroPoint system can be adapted to other focal surgeries in other organisms.
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Upon peripheral nervous system (PNS) injury, severed axons undergo rapid SARM1-dependent Wallerian degeneration (WD). In mammals, the role of SARM1 in PNS regeneration, however, is unknown. Here we demonstrate that Sarm1 is not required for axotomy induced activation of neuron-intrinsic growth programs and axonal growth into a nerve crush site. However, in the distal nerve, Sarm1 is necessary for the timely induction of the Schwann cell (SC) repair response, nerve inflammation, myelin clearance, and regeneration of sensory and motor axons. In Sarm1-/- mice, regenerated fibers exhibit reduced axon caliber, defective nerve conduction, and recovery of motor function is delayed. The growth hostile environment of Sarm1-/- distal nerve tissue was demonstrated by grafting of Sarm1-/- nerve into WT recipients. SC lineage tracing in injured WT and Sarm1-/- mice revealed morphological differences. In the Sarm1-/- distal nerve, the appearance of p75NTR+, c-Jun+ SCs is significantly delayed. Ex vivo, p75NTR and c-Jun upregulation in Sarm1-/- nerves can be rescued by pharmacological inhibition of ErbB kinase. Together, our studies show that Sarm1 is not necessary for the activation of neuron intrinsic growth programs but in the distal nerve is required for the orchestration of cellular programs that underlie rapid axon extension.
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Axotomized spinal motoneurons (MNs) lose presynaptic inputs following peripheral nerve injury; however, the cellular mechanisms that lead to this form of synapse loss are currently unknown. Here, we delineate a critical role for neuronal kinase dual leucine zipper kinase (DLK)/MAP3K12, which becomes activated in axotomized neurons. Studies with conditional knockout mice indicate that DLK signaling activation in injured MNs triggers the induction of phagocytic microglia and synapse loss. Aspects of the DLK-regulated response include expression of C1q first from the axotomized MN and then later in surrounding microglia, which subsequently phagocytose presynaptic components of upstream synapses. Pharmacological ablation of microglia inhibits the loss of cholinergic C boutons from axotomized MNs. Together, the observations implicate a neuronal mechanism, governed by the DLK, in the induction of inflammation and the removal of synapses.
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Neurônios Motores , Sinapses , Animais , Camundongos , Transdução de Sinais , Ativação do Complemento , Terminações Pré-Sinápticas , Camundongos KnockoutRESUMO
Introduction: The degeneration of injured axons is driven by conserved molecules, including the sterile armadillo TIR domain-containing protein SARM1, the cJun N-terminal kinase JNK, and regulators of these proteins. These molecules are also implicated in the regulation of synapse development though the mechanistic relationship of their functions in degeneration vs. development is poorly understood. Results and discussion: Here, we uncover disparate functional relationships between SARM1 and the transmembrane protein Raw in the regulation of Wallerian degeneration and synaptic growth in motoneurons of Drosophila melanogaster. Our genetic data suggest that Raw antagonizes the downstream output MAP kinase signaling mediated by Drosophila SARM1 (dSarm). This relationship is revealed by dramatic synaptic overgrowth phenotypes at the larval neuromuscular junction when motoneurons are depleted for Raw or overexpress dSarm. While Raw antagonizes the downstream output of dSarm to regulate synaptic growth, it shows an opposite functional relationship with dSarm for axonal degeneration. Loss of Raw leads to decreased levels of dSarm in axons and delayed axonal degeneration that is rescued by overexpression of dSarm, supporting a model that Raw promotes the activation of dSarm in axons. However, inhibiting Fos also decreases dSarm levels in axons but has the opposite outcome of enabling Wallerian degeneration. The combined genetic data suggest that Raw, dSarm, and Fos influence each other's functions through multiple points of regulation to control the structure of synaptic terminals and the resilience of axons to degeneration.
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The exposure of microorganisms to conventional plastics is a relatively recent occurrence, affording limited time for evolutionary adaptation. As part of the EU-funded project BioICEP, this study delves into the plastic degradation potential of microorganisms isolated from sites with prolonged plastic pollution, such as plastic-polluted forests, biopolymer-contaminated soil, oil-contaminated soil, municipal landfill, but also a distinctive soil sample with plastic pieces buried three decades ago. Additionally, samples from Arthropoda species were investigated. In total, 150 strains were isolated and screened for the ability to use plastic-related substrates (Impranil dispersions, polyethylene terephthalate, terephthalic acid, and bis(2-hydroxyethyl) terephthalate). Twenty isolates selected based on their ability to grow on various substrates were identified as Streptomyces, Bacillus, Enterococcus, and Pseudomonas spp. Morphological features were recorded, and the 16S rRNA sequence was employed to construct a phylogenetic tree. Subsequent assessments unveiled that 5 out of the 20 strains displayed the capability to produce polyhydroxyalkanoates, utilizing pre-treated post-consumer PET samples. With Priestia sp. DG69 and Neobacillus sp. DG40 emerging as the most successful producers (4.14% and 3.34% of PHA, respectively), these strains are poised for further utilization in upcycling purposes, laying the foundation for the development of sustainable strategies for plastic waste management.
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ß-glucans are a large class of complex polysaccharides found in abundant sources. Our dietary sources of ß-glucans are cereals that include oats and barley, and non-cereal sources can consist of mushrooms, microalgae, bacteria, and seaweeds. There is substantial clinical interest in ß-glucans; as they can be used for a variety of diseases including cancer and cardiovascular conditions. Suitable sources of ß-glucans for biopharmaceutical applications include bacteria, microalgae, mycelium, and yeast. Environmental factors including culture medium can influence the biomass and ultimately ß-glucan content. Therefore, cultivation conditions for the above organisms can be controlled for sustainable enhanced production of ß-glucans. This review discusses the various sources of ß-glucans and their cultivation conditions that may be optimised to exploit sustainable production. Finally, this article discusses the immune-modulatory potential of ß-glucans from these sources.
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Agaricales , Neoplasias , beta-Glucanas , Humanos , Imunidade , Saccharomyces cerevisiae , Preparações FarmacêuticasRESUMO
INTRODUCTION: Complex Regional Pain Syndrome (CRPS) is a disabling and distressing chronic pain condition characterised by a range of sensory, motor, autonomic and trophic symptoms. Guidelines recommend early referral for therapies that promote movement of the painful limb. However, evidence suggests a lack of defined therapy pathways for CRPS. AIMS: The current study aims to explore CRPS therapy management in centres of excellence in England, and outside of these settings, to understand what facilitates and hinders best practice. The overall aim is to develop a draft stratified package of care to expedite patient access to optimal CRPS therapy across the management pathway. METHODS AND ANALYSIS: Semi-structured interviews will be conducted with therapists working in CRPS centres of excellence and with therapists in other settings. Observations of therapy interventions in CRPS centres of excellence and interviews with patients who have received this care, will also help to identify potential key care package components. Interview data will be analysed using thematic analysis, mapped to the Theoretical Domains Framework (TDF), and Intervention Mapping Adapt (IMA) framework. Observations will be described and documented using the TDF headings. CONCLUSION: A triangulation protocol for qualitative health research will be used to integrate all data. Online stakeholder events will be held using consensus methods to agree a draft package of care for future implementation following further refinement, testing and evaluation. CLINICAL TRIAL REGISTRATION: The trial was registered with ISRCTN registry on 24 February 2022 (ISRCTN16917807).
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Dor Crônica , Síndromes da Dor Regional Complexa , Humanos , Dor Crônica/terapia , Síndromes da Dor Regional Complexa/terapia , Síndromes da Dor Regional Complexa/diagnóstico , Procedimentos Clínicos , Inglaterra , Estudos Observacionais como Assunto , Pesquisa QualitativaRESUMO
A prospective, one-armed, safety non-inferiority trial with historical controls was performed at a single-center, quaternary, children's hospital. Inclusion criteria were children aged 3 months-18 years after pediatric cardiac surgery resulting in a two-ventricle repair between 7/2020 and 7/2021. Eligible patients were compared with patients from a 5-year historical period (selected using a database search). The intervention was that "regular risk" patients received no diuretics and pre-specified "high risk" patients received 5 days of twice per day furosemide at discharge. 61 Subjects received the intervention. None were readmitted for pleural effusions, though 1 subject was treated for a symptomatic pleural effusion with outpatient furosemide. The study was halted after an interim analysis demonstrated that 4 subjects were readmitted with pericardial effusion during the study period versus 2 during the historical control (2.9% versus 0.2%, P = 0.003). We found no evidence that limited post-discharge diuretics results in an increase in readmissions for pleural effusions. This conclusion is limited as not enough subjects were enrolled to definitively show that this strategy is not inferior to the historical practice. There was a statistically significant increase in readmissions for pericardial effusions after implementation of this study protocol which can lead to serious complications and requires further study before conclusions can be drawn regarding optimal diuretic regimens.
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Procedimentos Cirúrgicos Cardíacos , Derrame Pericárdico , Derrame Pleural , Criança , Humanos , Assistência ao Convalescente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Diuréticos/uso terapêutico , Furosemida/uso terapêutico , Alta do Paciente , Derrame Pericárdico/etiologia , Derrame Pleural/etiologia , Estudos ProspectivosRESUMO
Axons are considered to be particularly vulnerable components of the nervous system; impairments to a neuron's axon leads to an effective silencing of a neuron's ability to communicate with other cells. Nervous systems have therefore evolved plasticity mechanisms for adapting to axonal damage. These include acute mechanisms that promote the degeneration and clearance of damaged axons and, in some cases, the initiation of new axonal growth and synapse formation to rebuild lost connections. Here we review how these diverse processes are influenced by the therapeutically targetable enzyme SARM1. SARM1 catalyzes the breakdown of NAD+, which, when unmitigated, can lead to rundown of this essential metabolite and axonal degeneration. SARM1's enzymatic activity also triggers the activation of downstream signaling pathways, which manifest numerous functions for SARM1 in development, innate immunity and responses to injury. Here we will consider the multiple intersections between SARM1 and the injury signaling pathways that coordinate cellular adaptations to nervous system damage.
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Peixes , Animais , Linhagem Celular , Peixes/genética , Plasmídeos , Interferência de RNA , RNA Interferente Pequeno/genéticaRESUMO
Higher scrutiny is befalling public payors regarding drug costs and patient access to medications. These issues exist in a complex contractual environment where minimal oversight of pharmacy claim adjudication and reimbursement practices can occur. The complexity of prescription benefits, and the lack of defined expectations or accountability in the system contribute to a sense of frustration by the public. Key areas of improvement for this sector of the health care industry include legislative and regulatory shifts requiring ongoing analyses, reporting, and accountability of pharmacy benefit managers (PBMs) in order to improve payment transparency. These improvements will enable plans to eliminate misaligned incentives in the industry and drive value. Changes in public sector programs should be comprehensive in their approach so that the policy will result in a reduction in costs, enhanced patient access, better patient safety, and improved health outcomes.
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Assistência Farmacêutica , Medicamentos sob Prescrição , Custos de Medicamentos , Humanos , Seguro de Serviços Farmacêuticos , Saúde Pública , Estados UnidosRESUMO
A healthy population of mitochondria, maintained by proper fission, fusion, and degradation, is critical for the long-term survival and function of neurons. Here, our discovery of mitophagy intermediates in fission-impaired Drosophila neurons brings new perspective into the relationship between mitochondrial fission and mitophagy. Neurons lacking either the ataxia disease gene Vps13D or the dynamin related protein Drp1 contain enlarged mitochondria that are engaged with autophagy machinery and also lack matrix components. Reporter assays combined with genetic studies imply that mitophagy both initiates and is completed in Drp1 impaired neurons, but fails to complete in Vps13D impaired neurons, which accumulate compromised mitochondria within stalled mito-phagophores. Our findings imply that in fission-defective neurons, mitophagy becomes induced, and that the lipid channel containing protein Vps13D has separable functions in mitochondrial fission and phagophore elongation.