Publications by authors named "Andrea Portt"

Objective: To systematically synthesize evidence from a broad range of studies on the association between air pollution and migraine.

Background: Air pollution is a ubiquitous exposure that may trigger migraine attacks. There has been no systematic review of this possible association.

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Background: A few extraintestinal pathogenic (ExPEC) multilocus sequence types (STs) cause the majority of community-acquired urinary tract infections (UTIs). We examine the genomic epidemiology of major ExPEC lineages, specifically factors associated with intestinal acquisition.

Methods: A total of 385 women with UTI caused by across Canada were asked about their diet, travel, and other exposures.

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Bacterial colonization of the urogenital tract is limited by innate defenses, including the production of antimicrobial peptides (AMPs). Uropathogenic Escherichia coli (UPEC) resist AMP-killing to cause a range of urinary tract infections (UTIs) including asymptomatic bacteriuria, cystitis, pyelonephritis, and sepsis. UPEC strains have high genomic diversity and encode numerous virulence factors that differentiate them from non-UTI-causing strains, including ompT.

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Article Synopsis
  • Citrobacter rodentium is studied as a model for intestinal infections similar to those caused by harmful E. coli strains, utilizing TCSs to adapt to the host environment during infection.
  • Researchers identified 26 TCSs in C. rodentium, demonstrating they are all active during murine infections, with some TCS deletions leading to changes in virulence.
  • The study found that specific strains, like ΔarcA and ΔrcsB, showed reduced virulence, while ΔuvrY displayed increased virulence, suggesting a connection between these TCSs and the cell surface characteristics, which could inform future drug development strategies.
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Bacterial proteases are important virulence factors that inactivate host defense proteins and contribute to tissue destruction and bacterial dissemination. Outer membrane proteases of the omptin family, exemplified by Escherichia coli OmpT, are found in some Gram-negative bacteria. Omptins cleave a variety of substrates at the host-pathogen interface, including plasminogen and antimicrobial peptides.

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We investigated whether specific sequence types, and their shared virulence gene profiles, may be associated with both human and food animal reservoirs. A total of 600 Escherichia coli isolates were assembled from human (n=265) and food-animal (n=335) sources from overlapping geographic areas and time periods (2005-2010) in Canada. The entire collection was subjected to multilocus sequence typing and a subset of 286 E.

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This study identified and characterized enteropathogenic Escherichia coli (EPEC) in the Canadian food supply. Eighteen of 450 E. coli isolates from food animal sources were identified as atypical EPEC (aEPEC).

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The PhoPQ two-component system of the intracellular pathogen Salmonella enterica senses and controls resistance to alpha-helical antimicrobial peptides (AMPs) by regulating covalent modifications of lipid A. A homologue of the phoPQ operon was found in the genome of the murine enteric extracellular pathogen, Citrobacter rodentium. Here we report that C.

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Giardia lamblia is one of the most recognized waterborne protozoan parasites causing gastrointestinal disease. A simple but effective DNA extraction protocol for real-time PCR detection from surface water samples was developed in this study. Eleven protocols were compared, which consisted of freeze-thaw treatments (liquid N(2) and boiling water) and purification using the Qiagen DNeasy kit, together with different combinations of proteinase K, PVP360, GITC and Chelex 100 incubation.

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