Research Publications (Food Safety)

Deoxynivalenol (DON), a trichothecene mycotoxin that commonly contaminates cereal grains, is a public health concern because of its adverse effects on the gastrointestinal and immune systems. The objective of this study was to compare effects of DON on anorectic responses in aged (22 mos) and adult (3 mos) mice. Aged mice showed increased feed refusal with both acute i.p. (1 mg/kg and 5 mg/kg) and dietary (1, 2.5, 10 ppm) DON exposure in comparison to adult mice.

Hweh Fen Goh, Koshy Philip

Richard Lu, BobBrooke Herrera, Heather D. Eshleman, Yang Fu, Alexander Bloom, Zhigang Li, David B. Sacks, Marcia B. Goldberg

Jessica Jenkins Broglie, Brittny Alston, Chang Yang, Lun Ma, Audrey F. Adcock, Wei Chen, Liju Yang

Abstract

Acute hepatic necrosis was diagnosed in a dog. Gram staining and fluorescence in situ hybridization identified Salmonella enterica in the liver, subsequently confirmed as S. enterica serotype I 4,5,12:–:1,2. This is the first report of acute hepatic necrosis with liver failure caused by Salmonella in a dog.

We used an in vitro technique to investigate blood volumes required to detect bacteremia and fungemia with low concentrations of an organism. At 1 to 10 CFU/ml, Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, Listeria monocytogenes, Candida albicans, and Candida parapsilosis isolates were detected in volumes as low as 0.5 ml. Detection of Streptococcus agalactiae and detection of bacteremia at <1 CFU/ml were unreliable.

Detailed laboratory characterization of Escherichia coli O157 is essential to inform epidemiological investigations. This study assessed the utility of whole-genome sequencing (WGS) for outbreak detection and epidemiological surveillance of E. coli O157, and the data were used to identify discernible associations between genotypes and clinical outcomes. One hundred five E.

Hepatitis E virus (HEV) is considered a zoonotic infection in developed nations. A case of acute hepatitis E in a researcher following a scalpel injury while working on a pig prompted a seroepidemiologic study to identify potential modes of transmission and determine the seroprevalence of HEV among animal handlers at the institute.

The ability of Escherichia coli O157:H7 to induce cellular damage leading to disease in humans is related to numerous virulence factors, most notably the stx gene, encoding Shiga toxin (Stx) and carried by a bacteriophage. Loss of the Stx-encoding bacteriophage may occur during infection or culturing of the strain. Here, we collected stx-positive and stx-negative variants of E. coli O157:H7/NM (nonmotile) isolates from patients with gastrointestinal complaints.

Our objectives were to study the prevalence, risk factors for carriage, and transmission dynamics of extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae (ESBLPE) in a national survey of cattle. This was a point prevalence study conducted from July to October 2013 in Israel. Stool samples were collected from 1,226 cows in 123 sections on 40 farms of all production types.

Salmonella enterica serovar Typhimurium is an important foodborne human pathogen that often causes self-limiting but severe gastroenteritis. Prolonged excretion of S. Typhimurium after the infection can lead to secondary transmissions. However, little is known about within-host genomic variation in bacteria associated with asymptomatic shedding. Genomes of 35 longitudinal isolates of S.

The control of food-borne outbreaks caused by Listeria monocytogenes in humans relies on the timely identification of food or environmental sources and the differentiation of outbreak-related isolates from unrelated ones. This study illustrates the utility of whole-genome sequencing for examining the link between clinical and environmental isolates of L. monocytogenes associated with an outbreak of hospital-acquired listeriosis in Sydney, Australia.

Although new serotypes of enterohemorrhagic Escherichia coli (EHEC) emerge constantly, the mechanisms by which these new pathogens arise and the reasons emerging serotypes tend to carry more virulence genes than other E. coli are not understood. An insertion sequence (IS) excision enhancer (IEE) was discovered in EHEC O157:H7 that promoted the excision of IS3 family members and generating various genomic deletions.

Fluoroquinolones (FQs) are among the drugs of choice for treatment of Salmonella infections. However, fluoroquinolone resistance is increasing in Salmonella due to chromosomal mutations in the quinolone resistance-determining regions (QRDRs) of the topoisomerase genes gyrA, gyrB, parC, and parE and/or plasmid-mediated quinolone resistance (PMQR) mechanisms including qnr variants, aac(6')-Ib-cr, qepA, and oqxAB.

Detection of fluoroquinolone resistance in Salmonella enterica has become increasingly difficult due to evolving resistance mechanisms to this antimicrobial class in this organism. We evaluated two quinolone disks and five fluoroquinolone disks for their ability to act as a surrogate agent for the detection of fluoroquinolone resistance in a collection of 136 S. enterica isolates, including 111 with intermediate or resistant ciprofloxacin MICs mediated by a variety of resistance mechanisms.

Fluoroquinolone resistance is a serious and increasingly common problem in Salmonella. Two companion studies in this issue of the Journal of Clinical Microbiology (E. Deak, R. Skov, J. A. Hindler, and R. M. Humphries, J Clin Microbiol 53:3405–3410, 2015, http://dx.doi.org/10.1128/JCM.01393-15; R. Skov, E. Matuschek, M. Sjölund-Karlsson, J. Åhman, A. Petersen, M. Stegger, M. Torpdahl, and G.

Summary

Yue Zhang, Jason W. Tam, Patricio Mena, Adrianus W. M. van der Velden, James B. Bliska

Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods.

Based on the 2983 peanut samples from 122 counties in six provinces of China’s Yangtze River ecological region collected between 2009–2014, along with the dietary consumption data in Chinese resident nutrition and health survey reports from 2002 and 2004, dietary aflatoxin exposure and percentiles in the corresponding statistics were calculated by non-parametric probability assessment, Monte Carlo simulation and bootstrap sampling methods.

In 1991, 1999 and 2006, randomly selected individuals from the Danish Central Personal Register provided a serum sample. From individuals aged 30 years and above, 500 samples from each year were analysed for Campylobacter IgG, IgA and IgM antibodies using a direct ELISA method.

Jill F. Kerrigan, Daniel R. Engstrom, Donald Yee, Charles Sueper, Paul R. Erickson, Matthew Grandbois, Kristopher McNeill, William A. Arnold Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations.