Publications by authors named "Darby A"

Bacterial infections can substantially impact host metabolic health as a result of the direct and indirect demands of sustaining an immune response and of nutrient piracy by the pathogen itself. Drosophila melanogaster and other insects that survive a sublethal bacterial infection often carry substantial pathogen burdens for the remainder of life. In this study, we asked whether these chronic infections exact metabolic costs for the host, and how these costs scale with the severity of chronic infection.

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Article Synopsis
  • Endosymbiosis occurs when a microbe lives within a host, playing a key role in the evolution of complex life forms but its transition processes are not well understood.
  • The study examines the genus Arsenophonus, revealing that strains shifting from horizontal to vertical transmission have larger genomes due to the acquisition of new genetic features and the loss of defense systems against viral attacks.
  • The research suggests that endosymbiosis leads to a mix of genome expansion and eventual reduction as the microbe adapts to its host, enabling rapid genetic innovation before settling into a more stable state.
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The Drosophila adult midgut progenitor cells (AMPs) give rise to all cells in the adult midgut epithelium, including the intestinal stem cells (ISCs). While they share many characteristics with the ISCs, it remains unclear how they are generated in the early embryo. Here, we show that they arise from a population of endoderm cells, which exhibit multiple similarities with Drosophila neuroblasts.

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Article Synopsis
  • High-sugar diets in adult Drosophila melanogaster (fruit flies) increase their susceptibility to infections by specific Gram-negative bacteria, leading to a higher likelihood of death.
  • The study shows that these bacteria grow more quickly in flies consuming high sugar, particularly linked to hyperglycemia, which may provide additional carbon for bacterial growth.
  • Although flies on both diets activate immune response genes, those on high-sugar diets produce less of the necessary antimicrobial peptides (AMPs), suggesting that sugar overnutrition negatively affects the flies' immune function and alters infection dynamics.
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Background: SARS-CoV-2 remains rapidly evolving, and many biologically important genomic substitutions/indels have characterised novel SARS-CoV-2 lineages, which have emerged during successive global waves of the pandemic. Worldwide genomic sequencing has been able to monitor these waves, track transmission clusters, and examine viral evolution in real time to help inform healthcare policy. One school of thought is that an apparent greater than average divergence in an emerging lineage from contemporary variants may require persistent infection, for example in an immunocompromised host.

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During the COVID-19 pandemic, the introduction of non-pharmaceutical interventions (NPIs) resulted in an unprecedented reduction in the transmission of the respiratory syncytial virus (RSV), the predominant cause of bronchiolitis. As NPIs were eased, it was speculated that RSV transmission would return with an increase in the severity of bronchiolitis. In a large tertiary hospital, a dramatic reduction in the incidence of bronchiolitis was seen during the COVID-19 pandemic.

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Cardiac resynchronization therapy (CRT) can lead to marked symptom reduction and improved survival in selected patients with heart failure with reduced ejection fraction (HFrEF); however, many candidates for CRT based on clinical guidelines do not have a favorable response. A better way to identify patients expected to benefit from CRT that applies machine learning to accessible and cost-effective diagnostic tools such as the 12-lead electrocardiogram (ECG) could have a major impact on clinical care in HFrEF by helping providers personalize treatment strategies and avoid delays in initiation of other potentially beneficial treatments. This study addresses this need by demonstrating that a novel approach to ECG waveform analysis using functional principal component decomposition (FPCD) performs better than measures that require manual ECG analysis with the human eye and also at least as well as a previously validated but more expensive approach based on cardiac magnetic resonance (CMR).

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A 2022 canine gastroenteritis outbreak in the United Kingdom was associated with circulation of a new canine enteric coronavirus closely related to a 2020 variant with an additional spike gene recombination. The variants are unrelated to canine enteric coronavirus-like viruses associated with human disease but represent a model for coronavirus population adaptation.

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Background: Insect cell lines play a vital role in many aspects of research on disease vectors and agricultural pests. The tsetse fly Glossina morsitans morsitans is an important vector of salivarian trypanosomes in sub-Saharan Africa and, as such, is a major constraint on human health and agricultural development in the region.

Methods: Here, we report establishment and partial characterisation of a cell line, GMA/LULS61, derived from tissues of adult female G.

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Objective: Microbial keratitis (MK) is a significant cause of blindness in sub-Saharan Africa. We investigated the feasibility of using a novel corneal impression membrane (CIM) for obtaining and processing samples by culture, PCR and whole-genome sequencing (WGS) in patients presenting with suspected MK in Malawi.

Methods And Analysis: Samples were collected from patients presenting with suspected MK using a 12 mm diameter polytetrafluoroethylene CIM disc.

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Background: Trombiculid mites are globally distributed, highly diverse arachnids that largely lack molecular resources such as whole mitogenomes for the elucidation of taxonomic relationships. Trombiculid larvae (chiggers) parasitise vertebrates and can transmit bacteria (Orientia spp.) responsible for scrub typhus, a zoonotic febrile illness.

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The immunogenicity and effectiveness of oral rotavirus vaccines (ORVs) against severe rotavirus-associated gastroenteritis are impaired in low- and middle-income countries (LMICs) where the burden of disease is highest. Determining risk factors for impaired ORV response may help identify strategies to enhance vaccine effectiveness. In this study, we use metagenomic sequencing to provide a high-resolution taxonomic analysis of stool samples collected at 6 weeks of age (coinciding with the first ORV dose) during a prospective study of ORV immunogenicity in India and Malawi.

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An active immune response is energetically demanding and requires reallocation of nutrients to support resistance to and tolerance of infection. Insulin signaling is a critical global regulator of metabolism and whole-body homeostasis in response to nutrient availability and energetic needs, including those required for mobilization of energy in support of the immune system. In this review, we share findings that demonstrate interactions between innate immune activity and insulin signaling primarily in the insect model as well as other insects like and mosquitos.

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As the mechanism for worse prognosis after cardiac resynchronization therapy (CRT) upgrades in heart failure patients with RVP dependence (RVP-HF) has clinical implications for patient selection and CRT implementation approaches, this study's objective was to evaluate prognostic implications of cardiac magnetic resonance (CMR) findings and clinical factors in 102 HF patients (23.5% female, median age 66.5 years old, median follow-up 4.

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Insects that live exclusively on vertebrate blood utilize symbiotic bacteria as a source of essential compounds, e.g., B vitamins.

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Care that is organized around the principles of harm reduction and the movement for police and prison abolition has the potential to uproot and transform structural causes of harm and violence, in the interconnected crises of drug-related harm, policing, and punishment. The United States' crisis of overdose and drug-related harm and its system of policing and punishment are historically and empirically linked phenomena. The abandonment of people whose use of drugs leads to their premature death, in the form of an overdose, is directly and indirectly connected to wider systems of criminalization and incarceration that also produce premature suffering and death.

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The aim was to test the hypothesis that left ventricular (LV) and right ventricular (RV) activation from body surface electrical mapping (CardioInsight 252-electrode vest, Medtronic) identifies optimal cardiac resynchronization therapy (CRT) pacing strategies and outcomes in 30 patients. The LV80, RV80, and BIV80 were defined as the times to 80% LV, RV, or biventricular electrical activation. Smaller differences in the LV80 and RV80 (|LV80-RV80|) with synchronized LV pacing predicted better LV function post-CRT (p = 0.

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The innate immune system provides hosts with a crucial first line of defense against pathogens. While immune genes are often among the fastest evolving genes in the genome, in , antimicrobial peptides (AMPs) are notable exceptions. Instead, AMPs may be under balancing selection, such that over evolutionary timescales multiple alleles are maintained in populations.

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Article Synopsis
  • - Fleas not only cause itching and allergic reactions but are significant carriers of diseases like the plague and other bacterial infections, particularly in tropical regions.
  • - Researchers conducted a study in Malaysia, isolating various bacterial strains from fleas to analyze their genomes, which revealed unique features related to reproductive strategies and interactions with hosts.
  • - The findings suggest that some fleas carry pathogens that could switch hosts, indicating the need for further investigation into flea-borne diseases and their potential impact on human health.
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Globally Antimicrobial Resistance (AMR) constitutes a health crisis, particularly in developing countries, where infectious disease are commonly fatal. There is clear evidence for microbial exposure and infection transmission within the home. Personal and environmental hygiene are the best ways of reducing household infections thus decreasing the need for antibiotics and consequently diminishing AMR.

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Background: Maternal breastmilk is a source of pre- and pro-biotics that impact neonatal gut microbiota colonization. Because oral rotavirus vaccines (ORVs) are administered at a time when infants are often breastfed, breastmilk microbiota composition may have a direct or indirect influence on vaccine take and immunogenicity.

Methods: Using standardized methods across sites, we compared breastmilk microbiota composition in relation to geographic location and ORV response in cohorts prospectively followed from birth to 18 weeks of age in India (n = 307), Malawi (n = 119), and the United Kingdom ([UK] n = 60).

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Objectives: To understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission risks, perceived risks and the feasibility of risk mitigations from experimental mass cultural events before coronavirus disease 2019 (COVID-19) restrictions were lifted.

Design: Prospective, population-wide observational study.

Setting: Four events (two nightclubs, an outdoor music festival and a business conference) open to Liverpool City Region UK residents, requiring a negative lateral flow test (LFT) within the 36 h before the event, but not requiring social distancing or face-coverings.

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Background: The COG-UK hospital-onset COVID-19 infection (HOCI) trial evaluated the impact of SARS-CoV-2 whole-genome sequencing (WGS) on acute infection, prevention, and control (IPC) investigation of nosocomial transmission within hospitals.

Aim: To estimate the cost implications of using the information from the sequencing reporting tool (SRT), used to determine likelihood of nosocomial infection in IPC practice.

Methods: A micro-costing approach for SARS-CoV-2 WGS was conducted.

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Improving health and healthcare for people experiencing homelessness (PEH) has become a national research priority. It is critical for research related to homelessness to be guided by input from PEH themselves. We are a group of researchers and individuals who have personally experienced homelessness collaborating on a study focused on homelessness and housing.

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