Publications by authors named "Timothy J Wells"

This study explores the development and characterization of spray-dried composite microparticles consisting of levofloxacin (LVX, a broad-spectrum antibiotic), and ambroxol (AMB, a mucolytic agent that has antibacterial and antibiofilm properties), for the intended application of the drug against lower respiratory tract infections (LRTIs). A range of LVX to AMB mass ratios (1:1, 1:0.5, and 1:0.

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Natural killer (NK) cell function is regulated by a balance of activating and inhibitory signals. Tumor necrosis factor (TNF) is an inflammatory cytokine ubiquitous across homeostasis and disease, yet its role in regulation of NK cells remains unclear. Here, we find upregulation of the immune checkpoint protein, T cell immunoglobulin and mucin domain 3 (Tim3), is a biomarker of TNF signaling in NK cells during Salmonella Typhimurium infection.

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Infections caused by Gram-negative bacteria are leading causes of mortality worldwide. Due to the rise in antibiotic resistant strains, there is a desperate need for alternative strategies to control infections caused by these organisms. One such approach is the prevention of infection through vaccination.

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Introduction: The complex encompasses a group of gram-negative opportunistic pathogens that cause chronic lung infections in people with cystic fibrosis. Distinct from other respiratory pathogens, causes a unique clinical disease in a subset of patients known as 'cepacia syndrome', fulminant pneumonia accompanied by bacteraemia and sepsis with a mortality rate of up to 75%. Due to the bacteraemia associated with this disease, the mechanisms that allow to resist the bactericidal effects of serum complement-depending killing are vital.

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Antibody-dependent enhancement (ADE) of infectious disease is a phenomenon whereby host antibodies increase the severity of an infection. It is well established in viral infections but ADE also has an underappreciated role during bacterial, fungal and parasitic infections. ADE can occur during both primary infections and re-infections with the same or a related pathogen; therefore, understanding the underlying mechanisms of ADE is critical for understanding the pathogenesis and progression of many infectious diseases.

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Antibiotic resistance is a major public health threat, and alternatives to antibiotic therapy are urgently needed. Immunotherapy, particularly the blockade of inhibitory immune checkpoints, is a leading treatment option in cancer and autoimmunity. In this study, we used a murine model of Salmonella Typhimurium infection to investigate whether immune checkpoint blockade could be applied to bacterial infection.

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Background: Pseudomonas aeruginosa is a multidrug-resistant pathogen causing recalcitrant pulmonary infections in people with cystic fibrosis (pwCF). Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have been developed that partially correct the defective chloride channel driving disease. Despite the many clinical benefits, studies in adults have demonstrated that while P.

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Background: Pseudomonas aeruginosa is a frequent pathogen isolated from bacterial bloodstream infection (BSI) and is associated with high mortality. To survive in the blood, P aeruginosa must resist the bactericidal action of complement (ie, serum killing). Antibodies usually promote serum killing through the classical complement pathway; however, "cloaking antibodies" (cAbs) have been described, which paradoxically protect bacteria from serum killing.

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Article Synopsis
  • - The BCC (Burkholderia cepacia complex) consists of at least 22 genetically different gram-negative bacteria that live in various environments and can cause diseases in both plants and humans.
  • - Researchers studied an isolated pathogen from chronic lung infection patients, revealing that it has two separate evolutionary lineages and significant metabolic diversity related to different ecological roles.
  • - The study suggests recognizing one lineage as a new species due to its unique abilities in iron metabolism through siderophore synthesis, proposing it be named (sp. nov.).
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Purpose: Robust biomarkers that predict disease outcomes amongst COVID-19 patients are necessary for both patient triage and resource prioritisation. Numerous candidate biomarkers have been proposed for COVID-19. However, at present, there is no consensus on the best diagnostic approach to predict outcomes in infected patients.

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Reward based learning is broadly acknowledged to underpin the development and maintenance of addictive behaviour although the mechanism in sexual compulsivity is less understood. Using a Pavlovian-to-Instrumental Transfer (PIT) task we tested whether the motivational aspect of conditioned Pavlovian conditioned stimulus invigorated instrumental responding in relation to specific compatible monetary rewards. Performance on the task was analysed between two groups of males based on Low (N = 38) and High (N = 41) self-report online sexual behaviour (OSB).

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Immunotherapy has revolutionized cancer therapy by reactivating tumour-resident cytotoxic lymphocytes. More recently, immunotherapy has emerged to restore immunity against infectious agents, including bacterial infections. Immunotherapy primarily targets inhibitory pathways in T cells, however interest in other effector populations, such as natural killer (NK) cells, is growing.

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Article Synopsis
  • Cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) lead to frequent lung flare-ups, impacting patients' quality and length of life, but the role of specific bacteria in airway infections is not well understood.
  • Researchers developed a real-time PCR test to quickly identify and quantify certain bacteria from respiratory samples, validating its use on various cultures, including those from CF and COPD patients.
  • Whole-genome sequencing revealed a diversity of bacterial species in patients' lungs, with higher antibiotic resistance found in CF isolates, highlighting the need for better understanding of these bacteria in lung health and disease.
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A hallmark of Listeria (L.) monocytogenes pathogenesis is bacterial escape from maturing entry vacuoles, which is required for rapid bacterial replication in the host cell cytoplasm and cell-to-cell spread. The bacterial transcriptional activator PrfA controls expression of key virulence factors that enable exploitation of this intracellular niche.

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Pseudomonas aeruginosa is one of the principal pathogens implicated in respiratory infections of patients with cystic fibrosis (CF) and non-CF bronchiectasis. Previously, we demonstrated that impaired serum-mediated killing of P. aeruginosa was associated with increased severity of respiratory infections in patients with non-CF bronchiectasis.

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The emergence of multiantibiotic-resistant bacteria, often referred to as superbugs, is leading to infections that are increasingly difficult to treat. Further, bacteria have evolved mechanisms by which they subvert the immune response, meaning that even antibiotic-sensitive bacteria can persist through antibiotic therapy. For these reasons, a broad range of viable therapeutic alternatives or conjunctions to traditional antimicrobial therapy are urgently required to reduce the burden of disease threatened by antibiotic resistance.

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Background: Chronic Lung Allograft Dysfunction (CLAD) limits long-term survival following lung transplantation. Colonization of the allograft by Pseudomonas aeruginosa is associated with an increased risk of CLAD and inferior overall survival. Recent experimental data suggests that 'cloaking' antibodies targeting the O-antigen of the P.

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Unlabelled: The BAM complex in is composed of five proteins, BamA-E. BamA and BamD are essential for cell viability and are required for the assembly of β-barrel outer membrane proteins. Consequently, BamA and BamD are indispensable for secretion via the classical autotransporter pathway (Type 5a secretion).

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Antibody-dependent enhancement (ADE) of viral disease has been demonstrated for infections caused by flaviviruses and influenza viruses; however, antibodies that enhance bacterial disease are relatively unknown. In recent years, a few studies have directly linked antibodies with exacerbation of bacterial disease. This ADE of bacterial disease has been observed in mouse models and human patients with bacterial infections.

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Objective: ZAP-70 BALB/c (SKG) mice develop reactive arthritis (ReA) following infection with Chlamydia muridarum. Since intracellular pathogens enhance their replicative fitness in stressed host cells, we examined how myeloid cells infected with C muridarum drive arthritis.

Methods: SKG, Il17a-deficient SKG, and BALB/c female mice were infected with C muridarum or C muridarum luciferase in the genitals.

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Article Synopsis
  • The Gram-negative outer membrane protects bacteria from antibiotics, detergents, and environmental threats, aided by virulence factors like DolP, a lipoprotein crucial for maintaining membrane integrity.
  • DolP has a unique structure with two BON domains that help it bind to anionic phospholipids, which is vital for its function and localization during cell division.
  • Understanding DolP's structure opens up possibilities for new treatments aimed at breaking down the bacterial cell envelope, potentially making bacteria more vulnerable to antibiotics.
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Viruses and bacteria colonize hosts by invading epithelial barriers. Recent studies have shown that interactions between the microbiota, pathogens and the host can potentiate infection through poorly understood mechanisms. Here, we investigated whether diverse bacterial species could modulate virus internalization into host cells, often a rate-limiting step in establishing infections.

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Mutations in σ-regulated lipoproteins have previously been shown to impact bacterial viability under conditions of stress and during infection. YraP is conserved across a number of Gram-negative pathogens, including , where the homolog is a component of the Bexsero meningococcal group B vaccine. Investigations using laboratory-adapted K-12 have shown that mutants have elevated sensitivity to a range of compounds, including detergents and normally ineffective antibiotics.

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Uropathogenic (UPEC) is the most common cause of urinary tract infection, which in some patients can develop into life-threatening urosepsis. Serum resistance is a key virulence trait of strains that cause urosepsis. Recently, we identified a novel method of serum resistance in patients with lung infections, where patients possessed antibodies that inhibited complement-mediated killing (instead of protecting against infection).

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