Publications by authors named "Jeremy Brownlie"

Article Synopsis
  • Plant pathogens significantly reduce crop productivity, resulting in potential food shortages for humans and animals.
  • While chemical control is commonly used, its overuse leads to fungal resistance and environmental issues, making accurate detection of pathogens crucial for effective disease management.
  • The review highlights the limitations of traditional detection methods and emphasizes the promise of innovative nanoparticle-based biosensors, particularly electrochemical and optical technologies, in enhancing early pathogen detection and informing better management strategies.
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Background: Peripherally inserted central catheters are susceptible to microbial colonisation and subsequent biofilm formation, leading to central line-associated bloodstream infection, a serious peripherally inserted central catheter-related complication. Next-generation peripherally inserted central catheter biomaterials, such as hydrophobic materials (e.g.

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Neurogenesis is a persistent and essential feature of the adult mammalian hippocampus. Granular neurons generated from resident pools of stem or progenitor cells provide a mechanism for the formation and consolidation of new memories. Regulation of hippocampal neurogenesis is complex and multifaceted, and numerous signaling pathways converge to modulate cell proliferation, apoptosis, and clearance of cellular debris, as well as synaptic integration of newborn immature neurons.

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Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a method whereby live-cell flow cytometry is extended upon to analyze the multiple functions of P2X7 receptor activation in real-time. Using a time module installed on a flow cytometer, live-cell functionality can be assessed and plotted over a given time period to explore the kinetics of calcium influx, transmembrane pore formation, and phagocytosis.

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infections can present different phenotypes in hosts, including different forms of reproductive manipulation and antiviral protection, which may influence infection dynamics within host populations. In populations of two distinct strains coexist, each manipulating host reproduction: strain PanCI causes cytoplasmic incompatibility (CI), whereas strain PanMK causes male killing (MK). CI occurs when a -infected male mates with a female not infected with a compatible type of , leading to nonviable offspring.

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Wolbachia are endosymbiotic bacteria present in a wide range of invertebrates. Although their dramatic effects on host reproductive biology have been well studied, little is known about the effects of Wolbachia on the learning and memory capacity (LMC) of hosts, despite their distribution in the host nervous system, including brain. In this study, we found that Wolbachia infection significantly enhanced LMC in both Drosophila melanogaster and D.

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Identifying the signaling mechanisms that regulate adult neurogenesis is essential to understanding how the brain may respond to neuro-inflammatory events. P2X7 receptors can regulate pro-inflammatory responses, and in addition to their role as cation channels they can trigger cell death and mediate phagocytosis. How P2X7 receptors may regulate adult neurogenesis is currently unclear.

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Background: The formation of biofilms and subsequent encasement of bacterial cells in a complex matrix can enhance resistance to antimicrobials and sterilizing agents making these organisms difficult to eradicate and control. The aim of this study was to evaluate and compare the capacity of 40 E. coli O26 isolates of enterohemorrhagic E.

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Article Synopsis
  • E. coli O26 is the second most common enterohaemorrhagic E. coli serotype linked to foodborne illnesses in Australia and globally, prompting research into its survival against disinfectants, acids, and antimicrobials.
  • 86.4% of E. coli O26 isolates were found to be susceptible to all tested antimicrobials, with some disinfectants effectively inhibiting their growth while others were not.
  • The study concluded that while Australian E. coli O26 isolates exhibit diverse virulence traits, their survival responses to antimicrobials and disinfectants are consistent, suggesting that their resilience may help them persist on food contact surfaces.
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Transposable elements (TEs) have been recognized as potentially powerful drivers of genomic evolutionary change, but factors affecting their mobility and regulation remain poorly understood. Chaperones such as Hsp90 buffer environmental perturbations by regulating protein conformation, but are also part of the PIWI-interacting RNA pathway, which regulates genomic instability arising from mobile TEs in the germline. Stress-induced mutagenesis from TE movement could thus arise from functional trade-offs in the dual roles of Hsp90.

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Article Synopsis
  • Wolbachia are bacteria that infect about 40% of insect species, and some strains, like wMelPop, can significantly reduce the lifespan of Drosophila melanogaster flies by over-replicating.
  • Researchers found that while the "Octomom" gene cluster in wMelPop was thought to be linked to increased virulence, the relationship between its copy number and fly pathology is less straightforward than previously believed.
  • Rather than being dependent on Octomom copy number, the negative effects on fly lifespan are more strongly associated with rising temperatures, indicating that the virulence mechanisms of wMelPop involve multiple, complex factors.
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Elevated levels of reactive oxygen species (ROS) provide protection against virus-induced mortality in Drosophila. In addition to contributing to oxidative stress, ROS are known to activate a number of signalling pathways including the extracellular signal-regulated kinases (ERK) signalling cascade. It was recently shown that ERK signalling is important for resistance against viral replication and invasion in cultured Drosophila cells and the gut epithelium of adult flies.

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Hyaluronic acid (HA) is a polysaccharide found in the extracellular matrix of vertebrate epithelial, neural and connective tissues. Due to the high moisture retention, biocompatibility and viscoelasticity properties of this polymer, HA has become an important component of major pharmaceutical, biomedical and cosmetic products with high commercial value worldwide. Currently, large scale production of HA involves extraction from animal tissues as well as the use of bacterial expression systems in Streptococci.

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Article Synopsis
  • The study focused on how Wolbachia bacteria affect reproductive proteins in Drosophila melanogaster, particularly looking at changes in protein expression in the females’ reproductive organs after mating with infected males.
  • A total of 1317 proteins were analyzed, with 83 showing significant expression changes linked to metabolism, immunity, and reproduction due to Wolbachia infection.
  • The research suggests that altered expression of seminal fluid proteins may contribute to cytoplasmic incompatibility, impacting embryonic development, and highlights potential proteins for further investigation into Wolbachia-host interactions.
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Article Synopsis
  • Wolbachia bacteria infect about 40% of insect species and are known for manipulating host reproductive systems, but their effects on behavior are less understood.
  • A specific strain of Wolbachia was found to reduce aggressive behavior in male Drosophila melanogaster flies, which is important for mate competition.
  • Research showed that this behavioral change is linked to lower levels of octopamine, a neurotransmitter that affects aggression, due to the downregulation of crucial genes in the octopamine biosynthesis pathway.
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Wolbachia mediates antiviral protection in insect hosts and is being developed as a potential biocontrol agent to reduce the spread of insect-vectored viruses. Definition of the molecular mechanism that generates protection is important for understanding the tripartite interaction between host insect, Wolbachia, and virus. Elevated oxidative stress was previously reported for a mosquito line experimentally infected with Wolbachia, suggesting that oxidative stress is important for Wolbachia-mediated antiviral protection.

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Most strains of the widespread endosymbiotic bacterium Wolbachia pipientis are benign or behave as reproductive parasites. The pathogenic strain wMelPop is a striking exception, however: it overreplicates in its insect hosts and causes severe life shortening. The mechanism of this pathogenesis is currently unknown.

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Background: The endosymbiont Wolbachia pipientis causes diverse and sometimes dramatic phenotypes in its invertebrate hosts. Four Wolbachia strains sequenced to date indicate that the constitution of the genome is dynamic, but these strains are quite divergent and do not allow resolution of genome diversification over shorter time periods. We have sequenced the genome of the strain wBol1-b, found in the butterfly Hypolimnas bolina, which kills the male offspring of infected hosts during embyronic development and is closely related to the non-male-killing strain wPip from Culex pipiens.

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Wolbachia, a maternally transmitted endosymbiont of insects, is increasingly being seen as an effective biological control agent that can interfere with transmission of pathogens, including dengue virus. However, the mechanism of antiviral protection is not well understood. The density and distribution of Wolbachia in host tissues have been implicated as contributing factors by previous studies with both mosquitoes and flies.

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The outcome of microbial infection of insects is dependent not only on interactions between the host and pathogen, but also on the interactions between microbes that co-infect the host. Recently the maternally inherited endosymbiotic bacteria Wolbachia has been shown to protect insects from a range of microbial and eukaryotic pathogens. Mosquitoes experimentally infected with Wolbachia have upregulated immune responses and are protected from a number of pathogens including viruses, bacteria, Plasmodium and filarial nematodes.

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