A5013551932- Escherichia coli research studies
- Vibrio bacteria research studies
- Antibiotic Resistance in Bacteria
- Salmonella and Campylobacter epidemiology
- SARS-CoV-2 and COVID-19 Research
- Viral gastroenteritis research and epidemiology
- SARS-CoV-2 detection and testing
- Gut microbiota and health
- Streptococcal Infections and Treatments
- Influenza Virus Research Studies
- Microbial Community Ecology and Physiology
- Helicobacter pylori-related gastroenterology studies
- Respiratory viral infections research
- Pneumonia and Respiratory Infections
- Antimicrobial Resistance in Staphylococcus
- Tuberculosis Research and Epidemiology
- Mycobacterium research and diagnosis
- Environmental DNA in Biodiversity Studies
- Bacterial Genetics and Biotechnology
- Bacteriophages and microbial interactions
- Clostridium difficile and Clostridium perfringens research
- Genomics and Phylogenetic Studies
- Infectious Diseases and Tuberculosis
- Bacillus and Francisella bacterial research
- COVID-19 diagnosis using AI
University of Alberta
2018-2024
Women and Children’s Health Research Institute
2023-2024
Provincial Laboratory of Public Health
2018-2023
Alberta Hospital Edmonton
2018-2023
University of Alberta Hospital
2018-2020
University of British Columbia
2009-2019
BC Centre for Disease Control
2016-2019
Alberta Health Services
2019
Public Health Laboratory
2019
Canada's Michael Smith Genome Sciences Centre
2009-2016
Nitazoxanide (NTZ) exhibits broad-spectrum activity against anaerobic bacteria and parasites the ulcer-causing pathogen Helicobacter pylori. Here we show that NTZ is a noncompetitive inhibitor (K(i), 2 to 10 microM) of pyruvate:ferredoxin/flavodoxin oxidoreductases (PFORs) Trichomonas vaginalis, Entamoeba histolytica, Giardia intestinalis, Clostridium difficile, perfringens, H. pylori, Campylobacter jejuni weakly active pyruvate dehydrogenase Escherichia coli. To further mechanistic studies,...
ABSTRACT The location of Helicobacter pylori in the gastric mucosa mammals is defined by natural pH gradients within mucus, which are more alkaline proximal to mucosal epithelial cells and acidic toward lumen. We have used a microscope slide-based gradient assay video data collection system document pH-tactic behavior. In response hydrochloric acid (HCl), H. changes its swimming pattern from straight-line random arcing or circular patterns that move motile population away strong acid....
Host resistance to bacterial infections is thought be dictated by host genetic factors. Infections the natural murine enteric pathogen Citrobacter rodentium (used as a model of human enteropathogenic and enterohaemorrhagic E. coli infections) vary between mice strains, from mild self-resolving colonization in NIH Swiss lethality C3H/HeJ mice. However, no clear component had been shown responsible for differences observed with C. infections. Because intestinal microbiota important regulating...
The intestinal microbiota is composed of hundreds species bacteria, fungi and protozoa critical for numerous biological processes, such as nutrient acquisition, vitamin production, colonization resistance against bacterial pathogens. We studied the role on host to Salmonella enterica serovar Typhimurium-induced colitis. Using multiple antibiotic treatments in 129S1/SvImJ mice, we showed that disruption alters susceptibility infection. Although all caused similar increases pathogen...
Studies of environmental microbiota typically target only specific groups microorganisms, with most focusing on bacteria through taxonomic classification 16S rRNA gene sequences. For a more holistic understanding microbiome, strategy to characterize the viral, bacterial, and eukaryotic components is necessary. We developed method for metagenomic amplicon-based analysis freshwater samples involving concentration size-based separation eukaryotic, viral fractions. Next-generation sequencing...
Using a test-negative design, the Canadian Sentinel Practitioner Surveillance Network assessed interim 2018/19 vaccine effectiveness (VE) against predominant influenza A(H1N1)pdm09 viruses. Adjusted VE was 72% (95% confidence interval: 60 to 81) medically attended, laboratory-confirmed illness. This substantial protection observed in all age groups, notably young children who appeared be disproportionately affected. Sequence analysis identified heterogeneity emerging clade 6B.1 viruses but...
Enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. are noninvasive attaching effacing (A/E) bacterial pathogens that cause intestinal inflammation severe diarrheal disease. These utilize a type III secretion system to deliver effector proteins into host epithelial cells, modulating diverse cellular functions, including the release of chemokine interleukin-8 (IL-8). While studies have implicated effectors NleE (non-locus enterocyte effacement [LEE]-encoded E) NleH1 in...
ABSTRACT Autophagy is a process whereby double-membrane structure (autophagosome) engulfs unnecessary cytosolic proteins, organelles, and invading pathogens delivers them to the lysosome for degradation. We examined fate of Salmonella targeted by autophagy found that autophagy-targeted present in cytosol HeLa cells correlates with intracellular bacterial replication. Real-time analyses revealed subset extensively associates components p62 and/or LC3 replicates quickly, whereas intravacuolar...
IntroductionThe Canadian Sentinel Practitioner Surveillance Network reports vaccine effectiveness (VE) for the 2018/19 influenza A(H3N2) epidemic.AimTo explain a paradoxical signal of increased clade 3C.3a risk among 35-54-year-old vaccinees, we hypothesise childhood immunological imprinting and cohort effect following 1968 pandemic.MethodsWe assessed VE by test-negative design overall co-circulating clades 3C.2a1b 3C.3a. variation age in was compared with amino acid haemagglutinin...
SARS-CoV-2 variants of concern (VOCs) have emerged as a global threat to the COVID-19 pandemic response. We implemented combined approach quickly detect known VOCs while continuously monitoring for evolving mutations virus. To rapidly VOCs, two real-time reverse transcriptase PCR assays were designed and implemented, targeting spike gene H69/V70 deletion N501Y mutation. The mutation demonstrated accuracies 98.3% (95% CI 93.8 99.8) 100% 96.8 100), limits detection 1,089 294 copies/ml, percent...
Sputum smear microscopy is a common surrogate for tuberculosis infectiousness. Previous estimates that smear-negative patients contribute 13-20% of transmissions and are, on average, 20 to 25% as infectious smear-positive cases are understood be high. Herein, we use an ideal real-world setting, comprehensive dataset, new high-resolution techniques more accurately estimate the true transmission risk cases.We treated all adult culture-positive pulmonary TB diagnosed in province Alberta, Canada...
Enteropathogenic Escherichia coli, enterohemorrhagic E. and Citrobacter rodentium belong to the family of attaching effacing (A/E) bacterial pathogens. They intimately attach host intestinal epithelial cells, trigger effacement microvilli, cause diarrheal disease. Central their pathogenesis is a type III secretion system (T3SS) encoded by pathogenicity island called locus enterocyte (LEE). The T3SS used inject both LEE- non-LEE-encoded effector proteins into cell, where these effectors...
Abstract Background Risk factors for nosocomial COVID-19 outbreaks continue to evolve. The aim of this study was investigate a multi-ward outbreak between 1st September and 15th November 2020, occurring in setting without vaccination any healthcare workers or patients. Methods Outbreak report retrospective, matched case–control using incidence density sampling three cardiac wards an 1100-bed tertiary teaching hospital Calgary, Alberta, Canada. Patients were confirmed/probable cases...
ABSTRACT Pyruvate-dependent reduction of NADP has been demonstrated in cell extracts the human gastric pathogen Helicobacter pylori. However, is not a substrate purified pyruvate:ferredoxin oxidoreductase (PFOR), suggesting that other redox active enzymes mediate this reaction. Here we show fqrB (HP1164), which essential and highly conserved among epsilonproteobacteria, exhibits NADPH activity. FqrB was by nickel interaction chromatography following overexpression Escherichia coli . The...
Enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC EHEC respectively) are attaching effacing bacterial pathogens that cause devastating diarrhoeal disease worldwide. These depend on a type III secretion system, which functions as molecular syringe to translocate effector proteins directly into infected host cells. One of these effectors, NleC, was recently described zinc metalloprotease targets NF-κB Rel-A (p65) thus contributes dampening inflammatory signalling during EPEC...
Salmonella enterica serovars are Gram-negative bacterial pathogens responsible for human diseases including gastroenteritis and typhoid fever. After ingestion, cross the intestinal epithelial barrier, where they phagocytosed by macrophages dendritic cells, which then enables their spread to systemic sites during cases of use two type 3 secretion systems encoded pathogenicity islands (SPI) 1 2 inject virulence proteins into host cells modify cellular functions. SPI1 is involved in cell...
To cause disease, Salmonella enterica serovar Typhimurium requires two type III secretion systems that are encoded by pathogenicity islands 1 and 2 (SPI-1 -2). These serve to deliver specialized proteins (effectors) into the host cell cytosol. While importance of these effectors promote colonization replication within has been established, specific roles individual secreted in disease process not well understood. In this study, we used an vivo gallbladder epithelial infection model study...
The dissemination of antibiotic resistant bacteria from anthropogenic sources into the environment poses an emerging public health threat. Antibiotic resistance genes (ARGs) and gene-capturing systems such as integron-associated integrase (intI) play a key role in alterations microbial communities spread environment. In order to assess effect activities on watersheds southwestern British Columbia, presence putative was analyzed microbiome agricultural, urban influenced, protected watersheds....
Interim results from Canada's Sentinel Practitioner Surveillance Network show that during a season characterised by early co-circulation of influenza A and B viruses, the 2019/20 vaccine has provided substantial protection against medically-attended illness. Adjusted VE overall was 58% (95% confidence interval (CI): 47 to 66): 44% CI: 26 58) for A(H1N1)pdm09, 62% 37 77) A(H3N2) 69% 57 predominantly B/Victoria lineage.
A few extraintestinal pathogenic