Publications by authors named "David O'callaghan"

Introduction: Brucellosis, a zoonotic infectious disease caused by bacteria of the genus Brucella, remains a significant global health concern in many parts of the world. Traditional diagnostic methods, including serological tests, suffer from limitations, including low sensibility and high false-positive rates, emphasizing the need for improved diagnostic strategies. In this study, we aimed to optimize diagnostic accuracy by reevaluating serological tests and exploring novel diagnostic algorithms.

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  • - Sepsis is a severe response to infection that causes life-threatening organ dysfunction, highlighting the need for better understanding and new treatments for this global health issue.
  • - Researchers utilized high-throughput tandem mass spectrometry to analyze the plasma proteins of sepsis patients compared to other groups, collecting extensive data from over 2,600 samples to identify specific protein changes and disease features.
  • - The findings offer insights into the immune response to sepsis, helping to pinpoint subtypes of the condition, potential biomarkers for diagnosis, and paving the way for personalized treatment strategies.
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  • The pathogen is commonly found in cattle and primarily transmitted to humans via contaminated dairy products or contact with infected animals.
  • Whole genome sequencing was utilized to investigate the pathogen's global evolutionary history, revealing four major clades with distinct geographic origins and timelines.
  • The findings suggest an African origin for the pathogen, with its spread to the Middle East, Europe, and the Americas likely linked to cattle trade, especially during the European colonization era.
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  • Bacteria from the genus Brucella cause brucellosis, a serious disease affecting both animals and humans, and have been controversially merged with other unrelated bacterial species based on genomic findings.
  • Researchers argue this merger is inappropriate due to lack of thorough phylogenetic analysis and exclusion of expert opinions in brucellosis.
  • They warn that combining these groups could lead to confusion and risks in public health, particularly impacting those dealing with brucellosis in under-resourced regions, and call for keeping the Brucella genus distinct.
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Numerous genotyping techniques based on different principles and with different costs and levels of resolution are currently available for understanding the transmission dynamics of brucellosis worldwide. We aimed to compare the population structure of the genomes of 53 Brazilian Brucella abortus isolates using eight different genotyping methods: multiple-locus variable-number tandem-repeat analysis (MLVA8, MLVA11, MLVA16), multilocus sequence typing (MLST9, MLST21), core genome MLST (cgMLST) and two techniques based on single nucleotide polymorphism (SNP) detection (parSNP and NASP) from whole genomes. The strains were isolated from six different Brazilian states between 1977 and 2008 and had previously been analyzed using MLVA8, MLVA11, and MLVA16.

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A 29-year-old Brazilian illegal gold miner developed intermittent fever. Blood cultures were positive for Gram-negative coccobacilli and, after an initial misidentification by an automated identification system, the diagnosis of brucellosis caused by Brucella suis was confirmed. We hypothesize an association with domestic or wild swine exposure.

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Human brucellosis is a zoonoses caused by bacteria of the genus Brucella. Infection results in subacute or chronic debilitating disease with nonspecific clinical manifestations and is often associated with consuming unpasteurized dairy products. We report 2 cases of brucellosis in male patients who were hospitalized in distinct towns of French Guiana, an overseas territory of France located on the northeastern shore of South America.

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Bacteria use the twin arginine translocator (Tat) system to export folded proteins from the cytosol to the bacterial envelope or to the extracellular environment. As with most Gram-negative bacteria, the Tat system of the zoonotic pathogen Brucella spp. is encoded by a three-gene operon, Our attempts, using several different strategies, to create a Brucella suis strain 1330 mutant were all unsuccessful.

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  • * Strain 115 underwent antimicrobial susceptibility testing and was molecularly characterized through whole genome sequencing, revealing its classification as Pseudochrobactrum saccharolyticum.
  • * The findings emphasize the need for improved diagnostic methods for bovine brucellosis, advocating for the inclusion of specific gene sequencing in routine procedures to avoid misidentifications.
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The eukaryotic protein CD98hc (also known as 4F2, FRP-1, or SLC3A2) is a membrane glycoprotein and one of the heavy chains of the family of heterodimeric amino acids transporters. It can associate with any of 6 different light chains to form distinct amino acid transporters. CD98hc is also involved in mediation of intracellular integrin signaling.

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We report the first case of brucellosis caused by an isolate whose genome is identical that of a frog isolate from Texas, demonstrating the zoonotic potential of amphibian-type Brucella. Importantly, with such atypical Brucella, correct diagnosis cannot be performed using routine serological tests or identification methods.

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Brucellosis is a neglected zoonosis. It causes acute febrile illness and a potentially debilitating chronic infection in humans, and livestock infection has substantial socioeconomic impact. Over the past two decades, improvements have been made to better understand the various aspects of human and animal brucellosis.

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Purpose: Constipation can be a significant problem in critically unwell patients, associated with detrimental outcomes. Opioids are thought to contribute to the mechanism of bowel dysfunction. We tested if methylnaltrexone, a pure peripheral mu-opioid receptor antagonist, could reverse opioid-induced constipation.

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Despite the benefits, one in three older adults in Ireland has low activity levels. This study examined associations between the local social and built environment and physical activity of older adults to identify age-friendly factors that support physical activity among the aging population. Data were from the population-representative Healthy and Positive Ageing Initiative Age-Friendly City and Counties Survey (N = 10,540).

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Brucellosis is a zoonosis caused by bacteria of the Brucella genus. In ruminants, brucellosis causes abortion, followed by chronic infection and secretion of bacteria in milk. In humans, it usually presents as flu-like symptoms, with serious complications if untreated.

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The opportunistic pathogen Burkholderia cenocepacia is particularly life-threatening for cystic fibrosis (CF) patients. Chronic lung infections with these bacteria can rapidly develop into fatal pulmonary necrosis and septicaemia. We have recently shown that macrophages are a critical site for replication of B.

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spp. are responsible for brucellosis, a widespread zoonosis causing reproductive disorders in animals. Species-classification within this monophyletic genus is based on bacteriological and biochemical phenotyping.

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Brucella are highly infectious bacterial pathogens responsible for a severely debilitating zoonosis called brucellosis. Half of the human population worldwide is considered to live at risk of exposure, mostly in the poorest rural areas of the world. Prompt diagnosis of brucellosis is essential to prevent complications and to control epidemiology outbreaks, but identification of Brucella isolates may be hampered by the lack of rapid and cost-effective methods.

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Opportunistic pathogens are a worldwide cause of mortality and morbidity, and infections with intrinsically antibiotic-resistant pathogens have a large clinical, social and economic impact. Bacteria belonging to the complex (Bcc), ubiquitous in natural and industrial environments, are notorious pathogens for individuals with cystic fibrosis (CF). In addition, is emerging as the culprit of non-CF related, sometimes fatal infections.

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Bacteria of the Burkholderia cepacia complex (Bcc) can cause devastating pulmonary infections in cystic fibrosis (CF) patients, yet the precise mechanisms underlying inflammation, recurrent exacerbations and transition from chronic stages to acute infection and septicemia are not known. Bcc bacteria are generally believed to have a predominant extracellular biofilm life style in infected CF lungs, similar to Pseudomonas aeruginosa, but this has been challenged by clinical observations which show Bcc bacteria predominantly in macrophages. More recently, Bcc bacteria have emerged in nosocomial infections of patients hospitalized for reasons unrelated to CF.

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Background: Overweight and obesity is related to many health problems and diseases. The current obesity epidemic, which is a major health problem, is closely related to a lack of physical activity, high levels of sedentary behavior, and increased energy intake; with evidence to show increasing incidence of these issues in the younger population. Tackling obesity and its comorbid conditions requires a holistic approach encompassing attention on physical activity, healthy diet, and behavioral activation in order to enable and maintain meaningful and long-term weight loss and weight maintenance.

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are highly infectious bacterial pathogens responsible for brucellosis, a frequent worldwide zoonosis. The genus has recently expanded from 6 to 11 species, all of which were associated with mammals; The natural host range recently expanded to amphibians after some reports of atypical strains from frogs. Here we describe the first in depth phenotypic and genetic characterization of a strains isolated from a frog.

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Introduction: Gastrointestinal dysmotility and constipation are common problems in intensive care patients. The majority of critical care patients are sedated with opioids to facilitate tolerance of endotracheal tubes and mechanical ventilation, which inhibit gastrointestinal motility and lead to adverse outcomes. Methylnaltrexone is a peripheral opioid antagonist that does not cross the blood-brain barrier and can reverse the peripheral side effects of opioids without affecting the desired central properties.

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