The Role of the AggR Regulon in the Virulence of the Shiga Toxin-Producing Enteroaggregative Escherichia coli Epidemic O104:H4 Strain in Mice

An O104:H4 Shiga toxin (Stx)-producing enteroaggregative Escherichia coli (EAEC) strain caused a large outbreak of bloody diarrhea and the hemolytic uremic syndrome in 2011. We previously developed an ampicillin (Amp)-treated C57BL/6 mouse model to measure morbidity (weight loss) and mortality of mice orally infected with the prototype Stx-EAEC strain C227-11. Here, we hypothesized that mice fed C227-11 cured of the pAA plasmid or deleted for individual genes on that plasmid would display reduced virulence compared to animals given the wild-type (wt) strain. C227-11 cured of the pAA plasmid or deleted for the known pAA-encoded virulence genes aggR, aggA, sepA or aar were fed to Amp-treated C57BL/6 mice at doses of 1010-1011CFU. Infected animals were then either monitored for morbidity and lethality for 28 days or euthanized to determine intestinal pathology and colonization levels at selected times. The pAA-cured, aggR, and aggA mutants of strain C227-11 all showed reduced colonization at various intestinal sites. However, the aggR mutant was the only mutant attenuated for virulence as it showed both reduced morbidity and mortality. The aar mutant showed increased expression of the aggregative adherence fimbriae (AAF) and caused greater systemic effects in infected mice when compared to the C227-11 wt strain. However, unexpectedly, both the aggA and aar mutants displayed increased weight loss compared to wt. The sepA mutant did not exhibit altered morbidity or mortality in th...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research

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Conclusion: People who are overweight or obese are motivated to lose weight because of health issues and feeling more comfortable with their body. The opportunities for weight loss lie in creating habits, routines and structuring everyday life activities to facilitate a healthier lifestyle.Significance: The findings indicate that an occupational therapist should be part of weight-loss interventions. PMID: 32065553 [PubMed - as supplied by publisher]
Source: Scandinavian Journal of Occupational Therapy - Category: Occupational Health Tags: Scand J Occup Ther Source Type: research
This study highlights the need for a better understanding of the complex ecology and dynamics of fluoroquinolone resistance in C. jejuni in poultry environment and warrants an examination of fluoroquinolone-resistant C. jejuni strains recovered from the natural broiler chicken environment.
Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
Publication date: Available online 19 February 2020Source: Journal of Molecular BiologyAuthor(s): Madhu Nagaraj, Mumdooh Ahmed, Jeppe Lyngsø, Brian Stougaard Vad, Andreas Bøggild, Anne Fillipsen, Jan Skov Pedersen, Daniel Erik Otzen, Ümit AkbeyAbstractProtein fibrillation is traditionally associated with misfolding, loss of functional phenotype and gain of toxicity in neurodegenerative diseases. However, many organisms exploit fibrils in the form of functional amyloids (FA), as seen in bacteria such as E. coli, Salmonella, Bacillus and Pseudomonas. Here, we provide structural information and mechanistic ...
Source: Journal of Molecular Biology - Category: Molecular Biology Source Type: research
This study draws on the Planned Risk Information Seeking Model (PRISM) to assess Zika virus information seeking and systematic processing, paying particular attention to the relationship between perceived knowledge and knowledge insufficiency. Novel risks, such as Zika, provide an interesting context for examining whether information ‐seeking models, such as PRISM, are able to predict information seeking when available information is limited or scarce. A cross‐sectional, online study of men and women of childbearing age (N = 494) residing in the state of Florida was conducted. Our results provide some support for the P...
Source: Risk Analysis - Category: International Medicine & Public Health Authors: Tags: Original Research Article Source Type: research
Authors: Al-Mnaser AA, Woodward MJ Abstract In vitro studies aimed at studying the mechanism of action of carvacrol and oregano as natural anti-bacterial agents to control multiple antibiotic-resistant avian pathogenic Escherichia coli (APEC) strain O23:H52 isolated from chicken were performed. Derivatives with increased minimum inhibitory concentrations (MIC) to the phytochemicals were selected after growing Escherichia coli (E. coli) strain O23:H52 at sub-lethal concentrations of carvacrol and oregano for a period of 60 days. Whole-genome sequencing (WGS) of two derivatives revealed a missense mutation in cadC an...
Source: Polish Journal of Microbiology - Category: Microbiology Tags: Pol J Microbiol Source Type: research
AbstractThe authors evaluated, retrospectively, the endoscopic sleeve gastroplasty impact in seven HIV patients, regarding effectiveness and safety outcomes. The mean baseline body mass index (BMI) was 33.76  kg/m2. The mean baseline CD4+ cell count was 690.43 cells/mm3, and the baseline viral load was undetectable. After 6  months, absolute weight loss, percentage of excess weight loss, percentage total weight loss, and BMI reduction were 20.2 ± 2.6 kg, 85.5 ± 11.1%, 21.3 ± 2.4%, and 7.1 ± 0.8 kg/m2, respectively. No pa...
Source: Obesity Surgery - Category: Surgery Source Type: research
Publication date: Available online 19 February 2020Source: Journal of the American College of RadiologyAuthor(s): Soheil Kooraki, Melina Hosseiny, Lee Myers, Ali GholamrezanezhadAbstractIn December 2019, a novel coronavirus pneumonia was emerged in Wuhan, China. Since then, this highly contagious coronavirus has been spreading worldwide with a rapid rise in the number of death tolls. The novel coronavirus infected pneumonia (NCIP) is characterized by fever, fatigue, dry cough and dyspnea. A variety of chest imaging features have been reported, similar to those found in other types of coronavirus syndromes. The purpose of t...
Source: Journal of the American College of Radiology - Category: Radiology Source Type: research
Authors: Wang X, Zhang X, He J Abstract On December 31, 2019, the Wuhan Municipal Health Commission announced an outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), China is now at a critical period in the control of the epidemic. The Chinese Government has been taking a series of rapid, comprehensive, and effective prevention and control measures. As the pandemic has developed, a fact has become apparent: there is a serious dearth of emergency medical supplies, and especially an extreme shortage of personal protective equipment such as masks and medical protective clothing. This is one of the...
Source: BioScience Trends - Category: Biomedical Science Tags: Biosci Trends Source Type: research
The objective of this study was to evaluate the prevalence and characteristics of avian-origin mcr-1-harbouring Escherichia coli in Shandong Province, China. During 2017—2018, a total of 668 non-duplicate E. coli isolates were separately collected from 8eight large intensive poultry farms in Shandong Province. Antimicrobial susceptibility testing for 10 antimicrobial agents commonly used in farms was performed on all E. coli isolates by the agar dilution method; the mobile colistin resistance gene (mcr-1) gene was screened by PCR, and mcr-1 positive isolates were PCR-screened for antimicrobial resistance genes and ty...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
In April 2011, a food-poisoning outbreak caused by Escherichia coli O111 occurred in Toyama, Japan. A total of 326 patients had complaints of gastrointestinal symptoms, such as abdominal pain and bloody diarrhea. Thirty-four of these cases were diagnosed with hemolytic–uremic syndrome (HUS). In addition, 21 of these 34 HUS cases developed encephalopathy and five cases eventually died due to brain edema, encephalopathy, and HUS.
Source: International Journal of Infectious Diseases - Category: Infectious Diseases Authors: Tags: Case Report Source Type: research
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