Assessing the genomic relatedness and evolutionary rates of persistent verotoxigenic serotypes within a closed beef herd in Canada.

Verotoxigenic (VTEC) are food- and water-borne pathogens associated with both sporadic illness and outbreaks of enteric disease. While it is known that cattle are reservoirs of VTEC, little is known about the genomic variation of VTEC in cattle, and whether the variation in genomes reported for human outbreak strains is consistent with individual animal or group/herd sources of infection. A previous study of VTEC prevalence identified serotypes carried persistently by three consecutive cohorts of heifers within a closed herd of cattle.

Plasmid Distribution among from Livestock and Associated Wastewater: Unraveling Factors That Shape the Presence of Genes Conferring Third-Generation Cephalosporin Resistance.

A key concern with agricultural wastewater storage ponds is that they may provide an environment conducive for horizontal exchange of antibiotic resistance genes (ARGs), thereby facilitating the emergence of antibiotic resistant pathogens. Central to this exchange are mobile genetic elements like plasmids; yet, the factors shaping their presence in agricultural environments remain poorly understood. Here, using as a model bacterium, we examined genetic backgrounds and plasmid profiles of generic fecal and wastewater isolates and those possessing and genes (which confer resistance to third-generation cephalosporins) to delineate factors shaping the environmental persistence of plasmid-associated ARGs in beef cattle feedlots.

Sources of generic Escherichia coli and factors impacting guideline exceedances for food safety in an irrigation reservoir outlet and two canals.

Nearly half of all cases of foodborne illness are associated with plant-based foods such as leafy greens and raw flour. An important potential source of pathogen contamination along the food-production continuum is irrigation water, which has led to the implementation of increasingly stringent agricultural irrigation water quality requirements. To better understand factors impacting irrigation water quality, we investigated sources of generic Escherichia coli and how they varied temporally among different sampling sites.

Multi-Year Persistence of Verotoxigenic (VTEC) in a Closed Canadian Beef Herd: A Cohort Study.

In this study, fecal samples were collected from a closed beef herd in Alberta, Canada from 2012 to 2015. To limit serotype bias, which was observed in enrichment broth cultures, Verotoxigenic (VTEC) were isolated directly from samples using a hydrophobic grid-membrane filter verotoxin immunoblot assay. Overall VTEC isolation rates were similar for three different cohorts of yearling heifers on both an annual (68.

Zoonotic Fecal Pathogens and Antimicrobial Resistance in Canadian Petting Zoos.

This study aimed to better understand the potential public health risk associated with zoonotic pathogens in agricultural fairs and petting zoos in Canada. Prevalence of , Shiga toxin-producing (STEC) O157:H7, and top six non-O157 STEC serogroups in feces ( = 88), hide/feather ( = 36), and hand rail samples ( = 46) was assessed, as well as distributions of antimicrobial resistant (AMR) broad and extended-spectrum β-lactamase (ESBL)-producing . Prevalence of methicillin-resistant (MRSA) in pig nasal swabs ( = 4), and , , and in feces was also assessed.

Early executive function differences in infants born moderate-to-late preterm.

Individuals who are born very preterm (<32weeks gestation) show differential development of prefrontal cortex structure, function, and dependent behaviors, including executive function (EF) skills, beginning during late infancy and extending into adulthood. Preschool-aged children born moderate-to-late preterm (PT; 32-36weeks gestation) show smaller discrepancies in EF development, but it is unclear whether these differences first emerge during the early childhood years, when EF is rapidly developing, or if they arise from alterations in complex cognitive skills measurable in late infancy. In the current study, we examined whether differences in complex attention, memory, and inhibition skills (precursor skills to EF) are altered in healthy infants born moderate-to-late PT at 9-months corrected age.

Comparative accessory gene fingerprinting of surface water Escherichia coli reveals genetically diverse naturalized population.

Aims: To utilize comparative accessory gene fingerprinting to discriminate between naturalized and faecal Escherichia coli, with particular emphasis on strains from phylogroup B1.

Methods And Results: Fourteen accessory genes that were potentially ecotype-specific were selected on the basis of comparative genomic DNA sequence analysis between faecal and environmental strains and also using a literature-based strategy. PCR assays were designed for each gene, and used to screen 107 faecal strains from various hosts and 106 environmental strains from surface water and sediment.

The distribution of Salmonella enterica serovars and subtypes in surface water from five agricultural regions across Canada.

Serovar prevalence of the zoonotic pathogen, Salmonella enterica, was compared among 1624 surface water samples collected previously from five different Canadian agricultural watersheds over multiple years. Phagetyping, pulsed field gel electrophoresis (PFGE), and antimicrobial resistance subtyping assays were performed on serovars Enteritidis, Typhimurium, and Heidelberg. Serovars and subtypes from surface water were compared with those from animal feces, human sewage, and serovars reported to cause salmonellosis in Canadians.

A national investigation of the prevalence and diversity of thermophilic Campylobacter species in agricultural watersheds in Canada.

The occurrence and diversity of thermophilic Campylobacter species (C. jejuni, coli, and lari) were studied in water samples from four river basins located across Canada. These basins located in Quebec (Bras d'Henri), Alberta (Oldman), Ontario (South Nation), and British Columbia (Sumas) represented some of the most intensive farming areas in Canada for hog, beef cattle, dairy cattle, and poultry, respectively.

Long-term monitoring of waterborne pathogens and microbial source tracking markers in paired agricultural watersheds under controlled and conventional tile drainage management.

Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp.

Using SWAT, Bacteroidales microbial source tracking markers, and fecal indicator bacteria to predict waterborne pathogen occurrence in an agricultural watershed.

Developing the capability to predict pathogens in surface water is important for reducing the risk that such organisms pose to human health. In this study, three primary data source scenarios (measured stream flow and water quality, modelled stream flow and water quality, and host-associated Bacteroidales) are investigated within a Classification and Regression Tree Analysis (CART) framework for classifying pathogen (Escherichia coli 0157:H7, Salmonella, Campylobacter, Cryptosporidium, and Giardia) presence and absence (P/A) for a 178 km(2) agricultural watershed. To provide modelled data, a Soil Water Assessment Tool (SWAT) model was developed to predict stream flow, total suspended solids (TSS), total N and total P, and fecal indicator bacteria loads; however, the model was only successful for flow and total N and total P simulations, and did not accurately simulate TSS and indicator bacteria transport.

Bacteria, viruses, and parasites in an intermittent stream protected from and exposed to pasturing cattle: prevalence, densities, and quantitative microbial risk assessment.

Over 3500 individual water samples, for 131 sampling times, targeting waterborne pathogens/fecal indicator bacteria were collected during a 7-year period from 4 sites along an intermittent stream running through a small livestock pasture system with and without cattle access-to-stream restriction measures. The study assessed the impact of cattle pasturing/riparian zone protection on: pathogen (bacterial, viral, parasite) occurrence, concentrations of fecal indicators, and quantitative microbial risk assessments (QMRA) of the risk of Cryptosporidium, Giardia and Escherichia coli O157:H7 infection in humans. Methodologies were developed to compute QMRA mean risks on the basis of water samples exhibiting potentially human infectious Cryptosporidium and E.

Coherence among different microbial source tracking markers in a small agricultural stream with or without livestock exclusion practices.

Over 1,400 water samples were collected biweekly over 6 years from an intermittent stream protected and unprotected from pasturing cattle. The samples were monitored for host-specific Bacteroidales markers, Cryptosporidium species/genotypes, viruses and coliphages associated with humans or animals, and bacterial zoonotic pathogens. Ruminant Bacteroidales markers did not increase within the restricted cattle access reach of the stream, whereas the ruminant Bacteroidales marker increased significantly in the unrestricted cattle access reach.

A Canadian application of one health: integration of Salmonella data from various Canadian surveillance programs (2005-2010).

Most bacterial pathogens associated with human enteric illness have zoonotic origins and can be transmitted directly from animals to people or indirectly through food and water. This multitude of potential exposure routes and sources makes the epidemiology of these infectious agents complex. To better understand these illnesses and identify solutions to reduce human disease, an integrative approach like One Health is needed.

Quantitative multi-year elucidation of fecal sources of waterborne pathogen contamination in the South Nation River basin using bacteroidales microbial source tracking markers.

Over a seven-year period (2004-2010) 1095 water samples were obtained from the South Nation River basin at multiple watershed monitoring sites (Ontario, Canada). Real-time PCR using Bacteroidales specific markers was used to identify the origin (human (10% prevalence), ruminant (22%), pig (~2%), Canada goose (4%) and muskrat (7%)) of fecal pollution. In parallel, the distribution of fecal indicator bacteria and waterborne pathogens (Cryptosporidium oocysts, Giardia cysts, Escherichia coli O157:H7, Salmonella enterica and Campylobacter spp.

Spatiotemporal analysis of Cryptosporidium species/genotypes and relationships with other zoonotic pathogens in surface water from mixed-use watersheds.

Nearly 690 raw surface water samples were collected during a 6-year period from multiple watersheds in the South Nation River basin, Ontario, Canada. Cryptosporidium oocysts in water samples were enumerated, sequenced, and genotyped by detailed phylogenetic analysis. The resulting species and genotypes were assigned to broad, known host and human infection risk classes.

An enhanced technique combining pre-enrichment and passive filtration increases the isolation efficiency of Campylobacter jejuni and Campylobacter coli from water and animal fecal samples.

Improved isolation techniques from environmental water and animal samples are vital to understanding Campylobacter epidemiology. In this study, the efficiency of selective enrichment in Bolton Broth (BB) followed by plating on charcoal cefoperazone deoxycholate agar (CCDA) (conventional method) was compared with an approach combining BB enrichment and passive filtration (membrane method) adapted from a method previously developed for testing of broiler meat, in the isolation of thermophilic campylobacters from surface water and animal fecal samples. The conventional method led to recoveries of Campylobacter from 36.

Spatial and temporal drivers of zoonotic pathogen contamination of an agricultural watershed.

In regions where animal agriculture is prominent, such as southern Alberta, higher rates of gastrointestinal illness have been reported when compared with nonagricultural regions. This difference in the rate of illness is thought to be a result of increased zoonotic pathogen exposure through environmental sources such as water. In this study, temporal and spatial factors associated with bacterial pathogen contamination of the Oldman River, which transverses this region, were analyzed using classification and regression tree analysis.

Investigation of an Escherichia coli environmental benchmark for waterborne pathogens in agricultural watersheds in Canada.

Canada's National Agri-Environmental Standards Initiative sought to develop an environmental benchmark for low-level waterborne pathogen occurrence in agricultural watersheds. A field study collected 902 water samples from 27 sites in four intensive agricultural watersheds across Canada from 2005 to 2007. Four of the sites were selected as reference sites away from livestock and human fecal pollution sources in each watershed.

Development and validation of a comparative genomic fingerprinting method for high-resolution genotyping of Campylobacter jejuni.

Campylobacter spp. are a leading cause of bacterial gastroenteritis worldwide. The need for molecular subtyping methods with enhanced discrimination in the context of surveillance- and outbreak-based epidemiologic investigations of Campylobacter spp.

Associations among pathogenic bacteria, parasites, and environmental and land use factors in multiple mixed-use watersheds.

Over a five year period (2004-08), 1171 surface water samples were collected from up to 24 sampling locations representing a wide range of stream orders, in a river basin in eastern Ontario, Canada. Water was analyzed for Cryptosporidium oocysts and Giardia cyst densities, the presence of Salmonella enterica subspecies enterica, Campylobacter spp., Listeria monocytogenes, and Escherichia coli O157:H7.

Cutaneous mycobacterial spindle cell pseudotumor: a potential mimic of soft tissue neoplasms.

A 55-year-old man with scleroderma treated with prednisone and etanercept presented with enlarging sporotrichoid nodules on the forearm. Microscopically, there were large circumscribed dermal and subcutaneous nodules of spindled and epithelioid cells, resembling a spindle cell neoplasm. Small foci of neutrophils were also present, and a subsequent Ziehl-Neelsen stain highlighted beaded acid-fast bacilli in the interstitium.

Flow cytometric evaluation of skin biopsies for mycosis fungoides.

Multicolor flow cytometry (FC) is indispensable for lymphoma diagnosis and classification, but its utility in evaluating skin biopsies for mycosis fungoides (MF) is not well established. We describe the largest series to date of skin biopsies evaluated by FC for MF (n = 33), and we compare the flow cytometric results with the histologic, molecular, and clinical findings. Abnormal T-cell populations were identified by FC in 14 of 18 patients (78%) having histologically confirmed MF and in no patient whose histology was negative or indeterminate for MF (n = 14).

Cutaneous pseudoglandular schwannoma: a case report of an unusual histopathologic variant.

Multiple morphologic variants of schwannomas have been described, including plexiform, cellular, epithelioid, ancient, and glandular schwannomas. Very rare variants of schwannoma contain gland-like structures formed by neoplastic Schwann cells. The differential diagnosis in these cases can be challenging and includes adnexal neoplasms, neurothekeoma, and vascular neoplasms.

Expression of prox1, lymphatic endothelial nuclear transcription factor, in Kaposiform hemangioendothelioma and tufted angioma.

Kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are rare tumors mainly occurring in early childhood. Our recent results showed that ectopic overexpression of human Prox1 gene, a lymphatic endothelial nuclear transcription factor, promoted an aggressive behavior in 2 murine models of KHE. This dramatic Prox1-induced phenotype prompted us to investigate immunohistochemical staining pattern of Prox1, podoplanin (D2-40), LYVE-1, and Prox1/CD34 as well as double immunofluorescent staining pattern of LYVE-1/CD31 in KHE and TA, compared with other pediatric vascular tumors.